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6.5 Detroit Diesel
02-28-2008, 16:03
Okay, seems like one thing after another right now. I have my Dad's 95'
6.5TD needing a new TC, doing a tranny swap on my brothers Jimmy, (700-R4), and now my own truck tranny is acting up. Here are the symptoms.

Goes into gear okay when engine not running.
When running, have to basically jam it into Lo or first gear. When driving won't downshift unless you really shove it. Won't drop into second at all.
I used to always start off in 1st. Now, unless I start in lo, it will crowhop a bit as soon as the clutch engages. Going through a drive-thru, it wouldn't come out of gear at first. When the clutch is in and it is acting sticky, I hear what sounds like a whirring noise. Reminds me of the noise a forklifts hydraulics make when the load is to heavy to lift.

The clutch reservoir has plenty of fluid, but the level barely changes at all when the clutch is pushed in.
The clutch, (and flywheel), are still rather new. Just over 20,000 miles on them. The truck has never been used for loads over 8,0000 lbs. Any ideas as to what this could be?
Aggravating to say the least as I also have roofing jobs to get to! :eek:
Thanks
Ben

a5150nut
02-28-2008, 19:30
Have you checked the trans to bell housing bolts to see if they are getting loose?

Other than that it could be a failin master or slave cylinder. Did you bleed the slave? Allen screw on top just ahead of where the line comes in.

6.5 Detroit Diesel
02-29-2008, 12:29
I will be checking it out. Thanks! Any other suggestions.

6.5 Detroit Diesel
02-29-2008, 16:19
Okay, so I disconnected the hose that runs up to the reservoir and plugged the bottom of the reservoir. I then filled up the reservoir with new fluid and tried the clutch. Basically no resistance, the clutch goes straight to the floor. So I am figuring that that is the problem, the master clutch cylinder. New one here and ready to go in! Also got a new slave cylinder as well as I am sure the old one needs to be replaced anyways. :D Hope that is the problem, though I can't see what else it could be!

Busted
02-29-2008, 18:51
dood, you shoulda called me up--I've got a brand spanking GM master cylinder in the box that I found in the back of that red and black truck I parted out . . . oh well.

Don't wreck your tranny :-)

6.5 Detroit Diesel
02-29-2008, 23:25
Nice dood. I had known back when I was out there that this was going to happen, we could have avoided it, eh? :D Oh well, sure you will find use in your tranny swaps. I gotta get the truck back together tomorrow though.

6.5 Detroit Diesel
03-01-2008, 15:44
New master clutch in. Put half a liter of fluid through trying to bleed out the stupid line. Still won't go in when running. If you jam it in, sounds like it is making light contact with the plates. Clutch won't stiffen up. Removed the inspection bolt and found that the fork moves around half an inch with pedal fully engaged. ?????????

a5150nut
03-01-2008, 20:09
Could be the pivot ball has gone away at the clutch fork. I've seen them wear clear through the fork. Sounds like time to pull the trans and check deeper. When moving the clutch line don't put any stress on it. DISCONECT AT BOTH ENDS before moving things around.

6.5 Detroit Diesel
03-01-2008, 21:44
Yea, sounds like it is time to move in. Did some research and found some people have had the fork actually bend after a while. Not sure how much of a possibility this could be though.

6.5 Detroit Diesel
03-04-2008, 17:17
Pulled the trans yesterday. Was to dark to see much so had to wait until today to get in close. The bellhousing is still attached to the block. I removed the throwout fork, bearing, and stud. The fork is cracked around the stud hole. The bearing is rather noisy. And the stud is worn down around the contact point. Also, there is apparently a keeper and a seat that go on the end of the stud that were no where in site. Anyone ever seen this before? Would the worn stud and missing seat cause it not to go into gear? I have pics.....

HH
03-04-2008, 21:26
YES. Replace the ball & fork, and may as well do the TB too. There is a zerk fitting on the bellhousing to grease that part, most people miss it. You will notice a huge difference.

6.5 Detroit Diesel
03-06-2008, 15:58
Well all parts are in. Seems to have done the trick. As for that grease fitting, I couldn't find it on the bellhousing. Is it covered by something? The TB is something that I want to keep well greased in the future.

HH
03-06-2008, 19:05
It for greasing the pivot ball. Should be right below where the pivot ball bolts in, IIRC, been a while since I greased mine.

Turbo Al
03-07-2008, 20:17
The fork and pivot need to be repaced as a unit and if there is any wear (sounds like you have a lot) on the pivot. These things usally last about 100,000 miles so you should be replacing them every time you do a clutch -- on the 1993 there is actually a grease fitting hiding in there as well.

1993 style outside slave cyl WARNING: DO NOT over tighten the bleed screw on the slave you will crack the housing. First take it out look at it and you will see that it is tappered to fit the hole so no great amount of torque is needed to seat it. Yes I broke the first one I did LOL.

OPPs guess I should have read page 2 before I posted -- yup still mind numbing drugs.

trbankii
03-08-2008, 11:04
Is it possible and/or recommended to update to the internal slave cylinder? I just really don't feel good about that plastic slave sitting there waiting to get hung up on a rock while off-road...

Turbo Al
03-08-2008, 15:49
I don't see why not. I have not had a later model NV4500 apart so don't know what is involved. On the bright side The under carraige of my 1993 looks like WW111 and have never hit the slave in years of harsh use hunting.
Al

trbankii
03-09-2008, 11:39
I do a certain amount of "rockcrawling" that just seems to be begging for one to hit the slave...

I figure that if I'm in there and replacing clutch, fork, pivot, etc, etc I might as well upgrade if possible... Suppose it would be a different master cylinder as well?

6.5 Detroit Diesel
03-12-2008, 15:55
Didn't know you could get an internal setup. A little late this time as I already have a new slave cylinder, but will keep in mind for next time.

trbankii
03-14-2008, 15:30
Damn... Knew that this project was coming up for me but had hoped that it would last a little longer. Driving home today I went to downshift and the clutch pedal went to the floor without disengaging... It had been getting harder to shift lately as well - pretty much as you were describing things at the beginning of the thread...

History: clutch line burst when I first went to look at the truck, seller replaced it; last summer the slave cylinder broke off where the clutch line connects to it; now this...

Knew I should have gone through and replaced everything at the beginning of the troubles, but last year was insane and I kept telling myself I'd patch things up to just get through the current crisis - which turned into the next crisis, and the next, and the next...

Sorry... Just venting... :)

trbankii
03-14-2008, 18:21
Question looking at this page: http://www.rockauto.com/catalog/x,carcode,1052514,parttype,1993

Of the last four ACDelco options I'm reading it as the first of the four is the clutch kit for the dual-mass flywheel, the second is if a single mass flywheel was installed by the dealer previously, the third is the dual-mass kit from the first one with the flywheel included, and the fourth is the single-mass kit from the second one with the flywheel included.

Based on the prices, I'm guessing that is correct but am I missing anything?

Have to pull the inspection plate tomorrow to see what shape things are in and what flywheel I have - although I am pretty much guessing it is the original dual-mass one.

6.5 Detroit Diesel
03-15-2008, 12:56
:DWhen the clutch and flywheel went on me originally, I talked with a few different places,(Tranny Shops, Mechanics), and the general consensus was that the single mass was better.

Now, on another note. Finally tried driving the truck today. It spent some time in the driveway as I did work on the engine. New glows and a girdle for the valve cover so it wouldn't leak anymore. :D Had my dad give me a hand bleeding out the clutch. Can't seem to get it to stiffen up. It will seem to have pressure, but then it will get softer. Very frustrating. Then when it is running, you still have to pull it into gear and then with the clutch pedal in, it is engaging and pulling truck forward. Once in gear with the clutch up, it is very solid contact. Won't go into overdrive either. I am trying to figure out if this is due to the slave cylinder not pushing in far enough. I am thinking of taking a pushrod and making a longer slave rod. I dunno.:mad:

trbankii
03-15-2008, 14:29
Hmmm... Hard to say. My Toyota you can adjust the slave cylinder linkage, but that isn't an option on this setup. You didn't specifically mention replacing the ball - you did, didn't you?

From what I've seen on the forums here it seems to be in favor of going single-mass. I sent an e-mail in to RockAuto to make sure that I was understanding the part numbers and the differences. Looks like that is the route I'm going to take.

6.5 Detroit Diesel
03-15-2008, 14:58
Are you talking about the ball stud that the fork pivots on? That I did replace. Really trying to figure this out as it is pissing me off. :mad: Oh well, in a month or two I will have forgotten about this whole thing and be driving the truck like nothing happened. :D

Up here in Canada I paid $1100 for a new flywheel and clutch pack. From what I have heard, there is just to many parts on the dual for starters, and then there was a few other things that people didn't like.

trbankii
03-16-2008, 11:02
Someone else will have to chime in on possible solutions - there doesn't seem to be many options for adjustment with the setup and if all parts (slave, ball pivot, and fork) are new there shouldn't be anything out of alignment...

RockAuto seems to be about $1100 with all the parts too. I saw a couple people mentioning South Bend Clutch as having a "preferred" setup so I e-mailed them for costs and options as they have a standard and a "performance" version - performance one has a Kevlar clutch disk.

trbankii
03-18-2008, 06:18
Just got the reply back from South Bend Clutch - wow! Their "performance" kit - with Kevlar clutch kit and flywheel included - is significantly less than the ACDelco "regular" setup with clutch kit and flywheel.

Unless anyone has any complaints or warnings, that looks like the direction I'm going to go with things.

They do recommend the transmission dampner talked about in other threads if you are switching from a DMF to a SMF. Have to decide whether I want to go for that or not. Actually, come to think of it, I wonder if that is included in the price of the ACDelco kit...

6.5 Detroit Diesel
03-19-2008, 19:08
Don't seem to remember putting that in.....

trbankii
03-19-2008, 19:41
Reading here and elsewhere, there are some who have added the tranny dampener based on it being a "recommended must-have" and others who haven't added it and see no difference... South Bend said that it is a dealer-only item.

6.5 Detroit Diesel
03-19-2008, 21:40
Now that I really think about it, I don't remember putting it in at all. I remember reading up on it, but then deciding that I could do without. Of course if it comes with the clutch kit........

trbankii
03-20-2008, 12:11
Might have some info for you, 6.5DD.

Talked to Peter at South Bend Clutch to order my replacement kit. Their kit comes with the flywheel, clutch disc, pressure plate, alignment tool, and throw-out bearing. I asked if there was anything else I'd need or that he'd recommend. He mentioned the tranny dampener again and also suggested replacing the fork and pivot ball - which I said was the reason I was going in there in the first place... He said that it was all pretty straightforward, but that there was one common mistake. He said to make sure that you put the clip and fork into the groove of the bearing together - don't split them apart. Without seeing it first hand, I can't quite picture what he was saying, but he said I'd understand when I saw it. But he said that people commonly split them apart and then have engagement problems.

Having done the replacement, if you can picture what he is saying and didn't keep them together that is likely your problem. Hope that helps!

RT
03-21-2008, 14:05
FWIW, I have been into my clutch 3 times. Once to do the rear main, then to do the input shaft seal and lastly to replace the fork, pivot and throughout bearing. Did the pilot bushing once. The disk was replaced at 118K by the PO right before I bought the truck. I am still using the ORIGINAL pressure plate and dual mass flywheel. Truck now has 252K on it. The master and slave blew when the fork/pivot went south. The bleeding process was VERY tedious and I experienced all the issues you are having. Keep working the clutch and try to bleed it. It will eventually start working normally. When the dual mass, etc. finally quits South Bend will get my business. Grease the pivot every time you do the chassis which for me is every 4K. RT

trbankii
03-22-2008, 11:08
RT, thanks for reminding me about the rear main seal and input seal - should replace those while I'm in there... Finishing putting my parts order together today.

trbankii
03-25-2008, 06:13
Got all my parts on order. The package from South Bend Clutch came yesterday - prompt shipping, carefully packaged, and Peter answered all my questions. I went with the heavy-duty Kevlar clutch - the SM flywheel, clutch, alignment tool, and bearings was under $700 shipped to my door. VERY pleased with the service.

Now just have to wait for the RockAuto and dealer items to get here and clear some time out to work on the truck. :)

trbankii
03-26-2008, 07:27
Talking with the GM parts counter person, the transmission dampener is nearly $500. But he included the TSB that recommends the dampener addition as follows (red, bold highlights mine):


#66-72-02B: MANUAL TRANSMISSION RATTLE NOISE AT IDLE - (Feb 1, 1997)

http://gsi.xw.gm.com/image_en_us/gif/000/999/999/999999995.gif REVISION: 01/27/97
THIS BULLETIN IS BEING REVISED TO ADD THE 1992-95 MODEL YEARS AND CHANGE PART NUMBERS. PLEASE DISCARD CORPORATE BULLETIN NUMBER 66-72-02 (SECTION 7 - TRANSMISSION). ---------------------------------------------------------------------- REVISION: 02/20/97
THIS BULLETIN IS BEING REVISED TO CHANGE A LABOR OPERATION NUMBER. PLEASE DISCARD CORPORATE BULLETIN NUMBER 66-72-02A (SECTION 7 - TRANSMISSION).
---------------------------------------------------------------------- SUBJECT: MANUAL TRANSMISSION RATTLE NOISE AT IDLE (INSTALL CONVENTIONAL FLYWHEEL)
MODELS: 1992-96 CHEVROLET AND GMC C/K 2-3 MODELS WITH 6.5L DIESEL ENGINE (VIN'S F, P - RPO'S L65, L49) AND NV4500 5 SPEED MANUAL TRANSMISSIONS (RPO'S MW3, MT8)

CONDITION:

SOME OWNERS MAY COMMENT ABOUT A RATTLE OR BANGING NOISE FROM THE TRANSMISSION WHILE THE ENGINE IS IDLING, THE CLUTCH ENGAGED (CLUTCH PEDAL RELEASED) AND THE TRANSMISSION IS IN NEUTRAL. THIS CONDITION IS MORE LIKELY TO OCCUR ON A VEHICLE THAT IDLES FOR PROLONGED PERIODS OF TIME. THIS RATTLE SHOULD NOT BE CONFUSED WITH NORMAL ROLL- OVER NOISE (TURNING BEARING/WHIRRING NOISE) WHICH IS GENERATED WHILE THE TRANSMISSION IS IN NEUTRAL, CLUTCH ENGAGED AND ENGINE IDLING.
CAUSE:

FAILURE OF THE HYSTERESIS DAMPER INSIDE THE DUAL MASS FLYWHEEL (DMF).
CORRECTION:

INSTALL A CONVENTIONAL FLYWHEEL, REVISED CLUTCH KIT AND A TRANSMISSION DAMPER. THESE REVISED PARTS ARE CURRENTLY INSTALLED IN 1997 MODEL TRUCKS.
IMPORTANT: INSTALLATION OF THESE PARTS WILL RESULT IN SOME DRIVE RATTLE (TRANSMISSION GROWL) WHEN DRIVING AT ABOUT 900 RPM OR LESS. NORMAL DMF SHUT-DOWN RATTLE WILL BE ELIMINATED IF THE CLUTCH IS DISENGAGED (PEDAL DEPRESSED), BUT RATTLE WILL OCCUR IF THE ENGINE IS SHUT-OFF WITH THE TRANSMISSION IN NEUTRAL AND THE CLUTCH ENGAGED (FOOT OFF PEDAL). THIS RATTLE IS FROM THE TRANSMISSION AND CAN NOT BE ELIMINATED BY TRANSMISSION REPAIR OR REPLACEMENT.

SERVICE PROCEDURE:

REFER TO THE APPROPRIATE YEAR SERVICE MANUAL SECTION 7C FOR CLUTCH REPLACEMENT PROCEDURES. WHEN INSTALLING THE NEW FLYWHEEL, THE RETAINING RING FROM THE DMF IS NOT USED.
4-WHEEL DRIVE: THE DAMPER IS INSTALLED BETWEEN THE TRANSMISSION AND THE TRANSFER CASE. TO INSTALL THE DAMPER, THE TRANSMISSION REAR EXTENSION HOUSING MUST BE REMOVED. REFER TO THE APPROPRIATE YEAR UNIT REPAIR MANUAL, SECTION 7B8, NV4500 MANUAL TRANSMISSION FOR DETAILS. WHEN INSTALLING THE DAMPER NUT, APPLY LOCTITE(R) 242, P/N 12345493, TO THE NUT THREADS AND TORQUE THE NUT TO 325 LB. FT. (441 N.M).
2-WHEEL DRIVE: THE DAMPER IS PART OF THE YOKE ASSEMBLY. REPLACEMENT OF THE YOKE IS REQUIRED. TO INSTALL THE YOKE, REFER TO THE APPROPRIATE YEAR UNIT REPAIR MANUAL, SECTION 7B8, NV4500 MANUAL TRANSMISSION. WHEN INSTALLING THE YOKE/DAMPER NUT, USE LOCTITE(R) 242, P/N 12345493, ON THE NUT THREADS AND TORQUE THE NUT TO 325 LB. FT. (441 N.M).
IMPORTANT: YOKE/DAMPER NOT USED ON 15,000 LB. MODELS

THE FOLLOWING FASTENER TIGHTENING SPECIFICATIONS SHOULD BE USED: -REAR EXTENSION-TO-CASE BOLTS 40 LB. FT. (54 N.M) -FLYWHEEL-TO-CRANKSHAFT BOLTS 65 LB. FT. (90 N.M) -PRESSURE PLATE-TO-FLYWHEEL BOLTS 25 LB. FT. (35 N.M)
NOTICE: THIS TRANSMISSION REQUIRES A SPECIAL SYNTHETIC LUBRICANT, P/N 12346190. DO NOT SUBSTITUTE ANY OTHER LUBRICANT AS INTERNAL TRANSMISSION DAMAGE MAY RESULT. TRANSMISSION CAPACITY IS 4 QUARTS (3.78L).

PARTS INFORMATION
P/N DESCRIPTION QTY 12375179 '92-95 K L49/L65 FLYWHEEL KIT 1 12375180 '92-95 C L49/L65 FLYWHEEL KIT 1 12375181 '96 K L49/L65 FLYWHEEL KIT 1 12375182 '96 C L49/L65 FLYWHEEL KIT 1 14061685 PILOT BEARING 1 12345493 THREAD LOCK SEALANT A/R 12346190 MANUAL TRANSMISSION FLUID 4
PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.
WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:
LABOR OPERATION DESCRIPTION LABOR TIME J1420 FLYWHEEL, MANUAL TRANSMISSION-REPLACE USE PUBLISHED K2160 TRANSMISSION YOKE, REPLACE (C) LABOR OPERATION K2764 TRANSMISSION REAR HOUSING, R & R (K) TIME
IMPORTANT: LABOR OPERATION IS CODED TO BASE VEHICLE COVERAGE IN THE WARRANTY SYSTEM.

FIGURES: 0 CAPTIONS: 0


If the only purpose of the dampener is to reduce noise at idle, I think that I can likely do without spending the extra $500 at this time - unless popular opinion is that the rattle is also enough of a vibration to cause durability issues...

6.5 Detroit Diesel
03-26-2008, 10:49
Seems like it eh? If there isn't going to be damage resulting from not installing the dampener, why spend the extra?
My truck is still sitting in the driveway awaiting some more TLC.

Hubert
03-27-2008, 19:13
I called around and asked too about SMF vs DMF before my tear down. Lots of parts houses list multiple versions on late 90's.

I had factory SMF. Its common for it to tear up the clutch disc hub and pilot bearing. I have had one disc hub failure. Previous owner had a bad input bearing. So pick your problem. Ahhh GM clutches you really have to love a stick with GM.

About half said dampener was required half said you could live w/o. Dodge does not incorporate a dampener with the 5.9 and its very very similar trans. I think the input shaft is different and a few other things but basically the same.

Bleed the clutch with slow steady pumps and or take a long break I think the constant pumping froths the fluid and its less effective.

Which pilot bearing did Southbend send and recommend? I read the bronze was preferred vs needle bearing.

trbankii
03-28-2008, 10:38
Southbend actually sends you a Kevlar pilot bearing - you can read their thoughts here: http://www.southbendclutch.com/kevlar.html

Hubert
03-28-2008, 11:33
I was hesitant to post anything but was curious about the Kevlar. On one thread a while back someone said the bronze was junk and iirc did not think much of the Kevlar one either.

I have read other good reports about the bronze. I have also read amazing stories of kevlar bushings in industrial applications. Not many like the needle bearing. Seeing it chewed up and gualled on the snout of my input shaft made me suspect it wasn't up to the task. Keep us posted how it stands up and how you like the SB clutch. Back when I was looking into it S.B. were still in favor of the DMF for the 6.5 but maybe with more history on the Kevlar pilot bushing they have leaned towards the SMF. They seem to be well respected for clutches.

FYI check out quad4x4 dot com for other good tech on the NV4500.

trbankii
03-28-2008, 12:57
Thanks for the tip, Hubert - I've dealt with Quad4x4 in the past with excellent results.

I'll definitely let people know how the South Bend parts hold up. On another board that I frequent, South Bend and the Kevlar stuff are said to be the only way to go.

trbankii
04-11-2008, 13:01
6.5DD - Did you ever get things resolved? What did you find was the problem?

6.5 Detroit Diesel
05-21-2008, 21:40
Sorry for not letting y'all know. I have been so stinkin' busy that the truck fell to the back burner and I ended up getting towed to a shop yesterday thinking that the clutch just had to be bled properly. $165 later the truck was back at my place. The mechanic figured that one of the fingers on the pressure plate was bent. It was $700 plus for them to do it, or myself. I pulled the t-case and tranny in a hour and a half. Sign that I have done it to much. :D Another 45 minutes later and the clutch pack was out and I was staring glumly at the exploded clutch plate. Exact same thing that happened when I first bought the truck. It doesn't make sense. The hardest work that I did with the truck was the 6,000+ lbs in the box the one time. I never towed with the truck, so I don't get why a clutch that should last an easy 60,000 miles would after barely 20,000. On the bright side, my buddy, who just had his NV4500 seize up after the rebuild shop failed to refill the oil, just pulled a tranny from the wreckers and is selling me the clutch pack for $50. So the problem has been found, I just have to put the stupid thing back together, again.
I have to edit the pics and then I can upload them

6.5 Detroit Diesel
05-21-2008, 21:44
Okay, here they are

trbankii
05-22-2008, 11:53
Had to read through the whole thread to see that you pulled the transmission, but not the bellhousing - I was wondering how you didn't see the clutch pack damage the last (recent) time you were in there.

What brand of clutch was that? The pictures are awfully small, but that looks "lightweight" compared to the South Bend clutch I bought...

Like you, this got shoved to the back burner as I had to take care of other issues. But I'm headed home today to pull the bellhousing and rest of the parts and then I can start reinstalling things.

Turbo Al
05-22-2008, 12:01
Sorry I have not been around -- been in and out of Hosp for two weeks now doing a million tests to try and save my leg. Looks like they got it figured out now -- I hope.


Most of the successfull change overs from DMF to SMF have been installing the dampner. On rare occassions (once that I know of) the clutch still came apart even with the dampner. I didn't install the clutch so don't know if it was installed correctly. NOTE: make dam sure you torque the pressure plate in an X pattern and in at least two stages. I have seen too many pressure plates that are loose on one side -- obvious indicator is that the pressure plate is blue on one side only.
I get approx. 65 to 70 thousand miles out of a clutch @ DMF.

Thanks for the tip on the Kevlar bushing I will order a couple and change it out with the new motor as soon as I am able to work on it.

Al

6.5 Detroit Diesel
05-22-2008, 13:26
I'll check it out and find out what brand it is. It does seem rather small though eh? This is only and 11" clutch disc. I seem to remember something about the Dodge NV4500 running something like a 13" disc?

trbankii
05-22-2008, 16:35
Al,

So you feel that the lack of the dampner on a SMF conversion will lead to damage? Crap... Another $500 out of pocket... Seems like the dampner is dealer only...

6.5DD, I'll get some pictures up of the clutch assembly that I picked up from South Bend.

vr1967
05-22-2008, 17:28
All 3 of my trucks with factory NV4500s came with 12" clutches, 2 are 6.5s and one has a factory 5.7L.
Not sure why you would have an 11" disc.

Edit after Turbo Al's post below: Both my 6.5s have single mass flywheels, not sure it matters, just stating for reference.

Turbo Al
05-22-2008, 18:40
I honestly don't know why the dampner is needed you would think the 16 springs on the assembly would make up for it but, yes if it was me I would go with the dampner. I have never had a solid flywheel -- two DMF -- so I have no direct exp working on a SMF but info from other DP members and a local trans shop tell me it is needed. I will never change mine over to SMF because I have had no problems at all with them in 200,000 miles. I personally think the SMF system is flawed with the clutch being the weak link.

The diameter of a DM clutch is also 12 inches and they have no springs in them, so I am not sure what application the 11 inch one is for.

Al

6.5 Detroit Diesel
05-22-2008, 21:24
This is kind of funny. I would like to know for next time, which is better? The reason I went with the SMF was that I was told that it was the stronger more durable one. But obviously there is some strong feeling otherwise. Whaddya say?

Turbo Al
05-22-2008, 23:35
Well it really depends on HOW you look at it. The DMF has six huge spings and big rubber snubbers and two piece flywheel to look after the vibrations, the DMF clutch has no springs on it what so ever. Also no dampner in the trans assembly.

The SMF has a clutch that has something like 12 or 16 (you would know) spings in it and like I said I think it is the weak link & depending on line of thought and a damper in trans assembly.

I have not had any trouble with the DMF at all (I have two one GM and one aftermarket) I rotate them every time I change the clutch (machine the surface on the one that is out)
I do go through a few more clutches than most because I do a lot of 4x4 ing some pretty long tows and have 3:43 gears which adds a bit more load on the clutch when I start it moving in 2nd gear -- never use first because it is extreamely low geared (1993) I get about 65 to 70 thou per clutch.
I have never had a SMF and don't intend to change over.

I do most of my own work and for a fact changing out the clutch is NOT a real easy job (trans weighs 200 lbs dry) but I have a system now that makes it as easy as possible.

I think if you add up all the parts the two different systems both come out to about the same price.

Al

vr1967
05-23-2008, 05:28
The last clutch I replaced on my 6.5 only had the normal 5-6 springs like the older GM clutches. I have used it for 15-20K so far with no trouble, alot of the time with my D5 cat behind it.
I picked it up at the local parts store and could give you the PN tomorrow or Sunday (I am out of town at the moment)
Not sure it is the proper one for the application, but I am friends with the owner, and he knew what it was going in and what it would be doing.

jeffscarstrucks
05-23-2008, 05:43
I came into this a little late but the pivot ball wear issue got me a few years ago as well. I was (and still am) carrying a spare master and slave cyl under the seat just in case. They are "self bleeding"....that is after you slowly pump the pedal about a hundred times! After 200k and two clutches I still have a DMF, but it does rattle a little when I am backing up a heavy trailer. I just tap the throttle and it quiets down. It will bite me one of these days. JEFF

Turbo Al
05-23-2008, 11:18
vr1967 that setup actually makes a LOT more sense to me than the recomended setup. Do you notice any more vibrations that the original setup?

Jeffscarstrucks, the only time my engine trans rattles is when the fuel filter is getting plugged up but I don't back up heavy trailers too often. Thanks for the "self bleeding" tip I will remember that next time I am alone.

Al

trbankii
05-23-2008, 17:15
The SMF setup I have definitely isn't 11"... ;)

The clutch plate is 12" and has ten springs in it. The flywheel is 14". Here is the picture of what I have.

Like 6.5DD, I went to the SMF because it seemed that everyone was saying that it was an improvement over the DMF. Also, everything I've ever worked on has the springs in the clutch - Ford Mustang, Toyota truck, Saab 900, Peterbilt - so the DMF with the springs was a bit funky to me when I first saw it...

Also, the Dodge uses a SMF in front of the NV4500...

I guess YMMV, but it just seemed like the logical course of action to get rid of the DMF...

6.5 Detroit Diesel
05-23-2008, 17:58
I am pretty sure that the brand I installed was DynaPak. I could be wrong, it probably is a 12".
What did you pay for the clutch pack? Including the flywheel?
I am hoping that I just got a defective clutch plate. :mad:
Now I know that I am not alone. I will be getting a basically new clutch setup in a week so it will be back together soon!

trbankii
05-23-2008, 18:22
From South Bend Clutch MU1931TZ - which includes the flywheel, pressure plate, heavy duty kevlar clutch, kevlar pilot bushing, TO bearing, and alignment tool.

Total was $692.58 shipped to my door.

93_Burrito
05-23-2008, 19:43
They are "self bleeding"....that is after you slowly pump the pedal about a hundred times!

What about using a MityVac for the bleeding? At least on the older style NV4500's with the external slave, I'd think this would work out real nice. Not sure about the newer version with internal slave...


Andy

trbankii
05-23-2008, 20:27
I've never had much luck with the MityVac... I've been using a Motive Products Power Bleeder but didn't have the adapter I needed to use it on the clutch master.

I ended up jacking up the front of the truck so that the bleed valve was elevated and then did the two-person bleed with my girlfriend. That worked very quickly.

jeffscarstrucks
05-24-2008, 07:31
I also use the Mity-vac for brakes but the self bleed method was actually right from the GM shop. On the rattle, I always figured that it was the inner section of the flywheel somehow rattling between the springs. It has done it for some time now and the last time I had it apart there was no odd wear so back in it went. I always figured that it had to do with the reverse gear ratio and a higher load being applied to the clutch itself as compared to starting out in low. Jeff
P.S. It is nice to come back to this forum where people actually think and converse about machines in a positive and knowledgable manner. I am working on a little 742 skid steer that I bought the other day and the first tool I used on it was a plasma cutter. Some people should not be allowed to use a metal butter kife, let alone tools....Thanks again, JEFF

trbankii
05-27-2008, 12:01
Hmmm... Do you think that the pivot ball may have been the issue? :D

http://www.thedieselpageforums.com/tdpforum/attachment.php?attachmentid=753&d=1211914876

Old one is on the left (if that wasn't obvious) and you can see the cracked seat in the fork behind the old and new one.

Curiously, as 6.5DD had mentioned with his situation, there is no sign of the seat and spring shown in the manual that are supposed to be on the threaded end of the pivot ball - and the pivot ball I got from the dealer did not come with them so I have to make another trip back there...

Finally, here is a picture of the zerk just below where the pivot ball screws into the bellhousing. I have to admit that I looked for it and did not see it before I had disassembled everything. Obviously the previous owner did not know about it either... In the photo above, you can see the hole towards the bottom of the pivot ball where the grease travels inside of the pivot ball to lubricate the ball at the fork. I'd assume that you would not want to pump gobs of grease into this and have it end up on the clutch itself...

http://www.thedieselpageforums.com/tdpforum/attachment.php?attachmentid=754&d=1211914876

Turbo Al
05-27-2008, 13:21
I have to say they stop working long before the get that bad so you must have a left leg as strong as an elephants!!

I honestly can't remember a spring in there BUT there are two different setup one for light duty and one for Heavy duty --- they don"t interchange.

Great Pictures

Al

trbankii
05-27-2008, 14:02
That's the funny thing - it seemed to work fine right up until it stopped working completely. At first, I thought I had blown the hydraulic line - which is what happened last summer. But then there wasn't the puddle of fluid like had happened that time...

Of course, since I bought this used and didn't know anything else, once I have this all fixed I'm going to probably think that it shifts smoother than melted butter! :D

And I should say "retainer spring" - the manual just says "spring." The pivot ball stud fits through the clutch fork and then a plastic seat and a spring clip fit on the stud to hold the fork in place.

JohnC
05-27-2008, 15:39
Don't over grease it. I put 1 pump from the grease gun every time I changed the oil filter. The owner's manual gives some ounce amount, but who measures? ;)

Turbo Al
05-27-2008, 16:21
Yes sping clip makes a lot more sense and It would be something I would put in without remembering it. I was 99% certain I didn't put in any kind of a spring in LOL, but felt like taking it apart (got lots of free time lol) to make sure ( :
Al

6.5 Detroit Diesel
05-31-2008, 08:43
Ya, the fork was cracked on the truck and the stud was worn right down like that too. The retainer had popped off inside as well. GM part only it would seem. Got the clutch and am putting it back together today hopefully.

6.5 Detroit Diesel
05-31-2008, 12:07
TRBANKII: Thanks for the picture. Armed with a scraper I attacked the bellhousing and discovered the fitting under a crusty layer of oil and dirt. :)
Clutch pack/housing is bolted up. Had to go to the dealer to get a missing housing stud, ($4!!!), but should have the rest of the tranny in within a few more hours. And then my beast will live again, finally. Just in time to drink up some of that $1.45/liter diesel. :mad:

6.5 Detroit Diesel
05-31-2008, 15:52
Thanks to all, the Evil Diesel lives again. Everything went in properly and the truck was started with a quick prayer and a minute later I was rollin' down the road.

trbankii
06-01-2008, 12:28
Good to hear!

Other things in life keep cropping up, but I really have to get mine back together this week...

trbankii
07-07-2008, 12:46
I won't go into the soap opera drama that has been keeping me from finishing this blasted project up... Suffice it to say that I'm still working on it...

Thought I was making headway over the weekend, but I cannot get the clutch to disengage far enough to be able to shift smoothly. I bled everything out and sticking a pick into the hole at the back of the bellhousing where the slave cylinder is located, I can see that the slave is moving the release fork about 5/8" to 3/4" - no idea if it should be more than that or not.

Pulled the transmission back off but so far still have the bellhousing on there. It is obviously not pressing against the fingers hard enough to disengage properly.

Just to confirm - this is how the release bearing goes on the fork (see photo)? I used the old fork and bearing as an example.

And there isn't a different fork that needs to be used when converting to the SMF from the DMF? When they went to the SMF in the '97s they also went to the internal slave "ring" setup, so I'm guessing you use the same fork you would use with the DMF?

a5150nut
07-07-2008, 19:52
What shape is the socket in the fork where the ball rides? And what shapee is the pivot ball in? I had rouble there once, new forlk and pivot ball fixed it. Mine is still DMF.

trbankii
07-07-2008, 20:22
That picture is the old fork and bearing for reference since the new stuff is all installed at the moment. Brand new fork, bearing, pivot ball, and retainer.

Check post #59 for my pictures of what shape the old stuff was in... :eek:

rhsub
07-08-2008, 00:26
Is clutch pedal hard or easy to push
If pedal is harder than normal the fork, ball or flywheel may not be right
When hand pressure is applied to fork and throw out bearing is touching clutch fingers, if you were to draw a imaginary line from the throwout brg to fork contact point, the fork to ball stud contact point and the fork to slave cylinder contact point, the slave cylinder contact point should be forward of the ball contact point by approx 1/2" (slightly more than 1/2 of slave cylinder travel), if the line is parallel or to the rear it will cause the fork to bind and not have enough throw out brg movement, bin there had this happen
I.ve seen this happen when the flywheel was machined to much
If possible bolt old clutch and flywheel together and compare measurement from crank mounting surface to fingers and compare to new assembly
Hope I explained this so you can tell what I am talking about
I'll check tomorrow if you need any more clarification
Ron
Ps yes that is the proper installation of the throwout brg to the fork

trbankii
07-08-2008, 06:59
Is clutch pedal hard or easy to push

Easy. Currently, the transmission is back out but I have the bellhousing and clutch all installed. I can look down through the hole in the floor as I apply the clutch and it seems that the fork is not pushing the throwout bearing in far enough.


If pedal is harder than normal the fork, ball or flywheel may not be right When hand pressure is applied to fork and throw out bearing is touching clutch fingers, if you were to draw a imaginary line ... if the line is parallel or to the rear it will cause the fork to bind and not have enough throw out brg movement, bin there had this happen I.ve seen this happen when the flywheel was machined to much

Brand new slave, fork, pivot ball, throwout bearing, clutch, and flywheel. I'm throwing a new master cylinder in today as it is the only part of the equation that is original at this point.


If possible bolt old clutch and flywheel together and compare measurement from crank mounting surface to fingers and compare to new assembly

Did that measurement last night trying to figure out if the old DMF to new SMF setups were different and required a different fork or something. They match exactly.


Hope I explained this so you can tell what I am talking about
I'll check tomorrow if you need any more clarification
Ron
Ps yes that is the proper installation of the throwout brg to the fork

Headed out there now to do the master cylinder. Other than that, I'm at a loss.

trbankii
07-08-2008, 11:33
Ok, replaced the master cylinder, bled it, and that seems to have solved the problem.

Should have done that from the start considering that 6.5DD also had that problem - not to mention that things like that should be replaced as systems (master, hydraulic line, slave) rather than components... If one part is going bad, likely that the other parts are worn too.

Now to get the rest of it back together and get the beast back on the road!

trbankii
07-15-2008, 10:49
Just wanted to thank everyone who posted here and offered help and suggestions. The beast is back together and under its own power once again.

Couldn't have done it without all you folk! ;)

otisd85
07-20-2012, 14:05
ill start with i realize this is a 4 year old thread.

any new updates? it seems some of you were having similar failures as me, and i was curious if your failures have continued, or resolved?

i have a 90 crewcab 4x4 with a 6.2 that had a th400 and i put a nv4500 from a 93 in it. i have had the clutch fail 4 times now in the last few years, every time i tear out the springs and the center hub comes loose, and the clutch will no longer disengage.

otisd85
07-20-2012, 14:07
another pic of the destroyed clutch

otisd85
07-20-2012, 14:08
and another

otisd85
07-20-2012, 14:10
another one

otisd85
07-20-2012, 14:12
then there is this pile of springs

otisd85
07-20-2012, 14:13
and the damage it did to the flywheel

trbankii
07-20-2012, 14:30
What brand clutch? I've had no issues since replacing mine with a South Bend four years (and one week, apparently) ago.

otisd85
07-20-2012, 15:02
i have been using a LUK from my local napa. i talked to a south bend rep the last time i had my clutch out. he said that he would love to sell me a clutch, but as long as im not tearing up the friction material, which i am not, a south bend clutch would not solve the center hub spring problem.

i have a solid mass flywheel for a 6.2 that was new when i did the swap. this time i had the trans and t case rebuilt, new hydraulics, and im trying to replace everything while im in there so i dont have this problem a fifth time. i have the fork and pivot ball coming from the dealer, i guess now its a special order part its supposed to be here middle of next week.

trbankii
07-20-2012, 18:48
Actually, parts from my South Bend clutch were LUK components.

I had swapped from the dual-mass flywheel to the solid flywheel when I replaced my clutch. I've seen pros and cons for each setup.

otisd85
07-20-2012, 22:23
i read through the thread again, you mentioned a "retainer spring" or plastic clip type thing in post 61. did that come with the new pivot ball from the dealership? or is that something i have to find separate? when i ordered the pivot ball, i asked about it and the parts guy said he thought he knew what i was talking about, but couldn't find it so it must come with the ball. he may be right, but he didn't sound very convincing, so i don't want to wait til next week to find out i still have another small part to find. if you got it somewhere else do you remember where you found it, or if it came from the stealership do you maybe still have the receipt with apart number?

trbankii
07-21-2012, 09:41
Had to go back through my pictures to see if I had one that showed the retainer clip. Here it is. I don't remember ordering anything separate, so I'm pretty sure that this came with the pivot ball. It screws/pushes onto the threaded end of the pivot ball.

otisd85
07-21-2012, 10:28
Thanks, I suppose I'll just have to hope the new pivot ball comes with it. At least now I have an idea what I'm looking for if it doesn't. Thanks again that helps alot.

Its kind of interesting to hear your southbend was a repackaged luk, and then to see my standard napa clutch its a luk also. Although you have the kevlar option, right?

otisd85
07-21-2012, 10:33
I also wanted to ask, did you ever end up using that dampner deal that was discussed back when you were in there?

trbankii
07-21-2012, 22:32
At the time, I did not get the dampener. Afterwards, I happened to find one at a good price, but never got around to tearing it all back apart again. I really haven't noticed any vibrations or other odd characteristics without it.