??? about the Allison

[mbrower]

I have a few questions I wish to present to the allison gods. First, does your truck need to be in tow/haul mode before you can use grade braking. I hardly ever tow in tow/haul but I feel the tranny braking when coming down a steep grade with the brake on. I thought it was the grade braking feature but now I am not sure and the operations manual don't cover it. The second question is what can one expect to pay to have the transmission rebuilt or replaced. Just thinking long term. Any help you can supply will be appredciated.
Thanks Mark

[hoot]

You are experiencing normal grade braking operation. It will "hold" gears without upshifting unless you accelerate and it will downshift moderately when braking on hills... all without being in tow/haul.

Tow haul simply modifies the parameters to allow the engine to wind out a bit more before upshifting and also locks the TC in all gears except first. Tow/haul also turns up the grade braking big time.

I don't have any idea what a rebuild will cost.

[SoCalDMAX]

Hoot is right on the money, great explanation.

RE: Rebuild,
Within the warr. period, it's obviously free.
After that, I'd call ATS and get their beefed valve body, torque converter and controller for $2,250. I imagine the total could reach $3,000 - $3,500. Probably comparable to getting any other AT rebuilt.

Are you planning on doing something that could result in catastrophic failure of a very strong tranny? Come on... don't be shy. ;)

Regards, Steve

[ 06-24-2002: Message edited by: SoCalDMAX ]</p>

[bluenote]

Mark-

The moron who was asking about these things over at RV.net wouldn't care if you got the facts here and relayed them there anyways. The truth (or intelligence for that matter) didn't seem to be high on his list. After the garbage he spewed at you, Lone Eagle, and then me when I tried to pin him down, I gave him up for the troll that he was. At least it made for an interesting thread/argument IMHO.

Just remember Mark, we're all in grave danger with our scary Allison transmissions! ;)

[mbrower]

Thanks Bluenote, I believe I'm going to give up with him and let that thread die. I just hate to see someone talk trash about something they don't even own and try to convince others to share thier opinion. I truly feel that when it's all said and done, the dmax/allison combo will be the best drivetrain ever put in a pick-up truck and those of us smart enough to see it will get the last laugh. smile.gif
Mark

[bluenote]

Mark-

My wife and I went back and read through the thread again, and both got quite a chuckle out of it. I wonder if the guy was drinking (seriously). He became less coherent and sensible as the thread wore on yesterday. I guess we can't convince them all.

For those of you saying HUH?, we had a fool going yesterday on another forum. He told us the Allison, particularly tow/haul, was dangerous and would cause accidents due to it's design. He also claimed it was a $2500 option and that it would be $6000 to repair/replace. He finally made the statement that Trailer Life magazine should have an expose' of the dangers of this tranny, or they would be held liable for any deaths caused by it.

What frightens me is that there is such a moron (drunk?) with a truck and big trailer driving around. tongue.gif

[SoCalDMAX]

Bluenote,

I went over and read that thread last nite after it was mentioned here. I gotta agree, that maroon was out there. :eek:

There was a little shred of reasoning: the thought that on an icy surface the downshifting of the Allison coupled with braking might be enough to break traction. But when you add in all of the variables like: what type of tire, how much ice, how much pin/tongue weight, speed, etc, then there's too much to guess at.

Not to mention that common sense could indicate installing chains, taking a different route or actually turning off tow/haul mode. ;)

His assertions of forum liability are ludicrous. It's thinking like that (it's everyone's fault but mine) that has led to this litiginous era we live in.

Oh, well. Back on topic, as much as I beat on this thing, I don't see any indication that I'll be using the Allison warranty anytime soon. ;)

Regards, Steve

[hoot]

Just remember, you shouldn't be driving, let alone towing on icy surfaces, especially going down hill.

If you have no choice then you better know what you're doing as with any vehicle in the same situation.

You should never use tow/haul in slippery conditions especially with a load.

I remember almost wiping out in a Chevy van years ago when driving down a steep snowy hill. I was too stupid to realize that downshifting the auto manually into 2nd would put me into a tail spin. I was lucky enough to have the presence of mind to quickly upshift again. I got back in control by simultaneously pumping my brakes and using the e-brake with the release handle pulled.

Bottom line, driving in slippery conditions requires awareness of the operation of the vehicle in question and lots of skill.

[bluenote]

I agree that a good downhill grade with icy roads can spell disaster, particularly when you're towing or hauling. I seldom use the tow/haul mode anyways, but may do so this summer on our vacation, as we'll see some real hills (no real big pulls happen here in Michigan driving). However, maybe I'm missing the point, but wouldn't towing down icy downhill grades with a manual transmission have similar potential dangers. I know the argument is that you can select a lower gear at the top of the hill, but you can do that with the auto too. Also, if the weight of the rig is pushing you faster than the tires wanna spin (depending on gear choice), you're gonna slide anyways. All this being said, maybe we could get that guy to start a class-action lawsuit on our behalf, just in case we all have an accident on the hills. :D

[ 06-25-2002: Message edited by: bluenote ]</p>

[Colorado Kid]

I'm not going to argue about tow/haul, but the Allison DOES cost $2,295 more than the ZF-6 speed in any given truck. When you add the Duramax or 8.1 to the truck you have a choice to make. One option is called M74, and about 95% of the people get it, it adds $1,200 to the retail price and is the Allison 1000 Automatic. The other option is called ML6, it subtracts $1,095 from the retail price and is the ZF6-650 Manual transmission. Go to kbb.com and check it out for yourself. Edmunds.com and my window sticker agree.

If you thought you got the Allison for $1,200 more than the manual trans I'm sorry, but it just isn't so. I think the Allison is great, and I know it has sold a lot of pickups...I've even talked a couple of folks into buying them, but when it came to my personal payments I couldn't justify the $$$$ just so that my wife would like my truck better. ;)

[SDWA]

I need some good humor, someone post the link to the thread, I couldn't find it...


Scott

[rvforfun]

Hey if the tow haul mode is dangerious? How about the 4 wheel steering? Which why do you turn the steering wheel in a slide/skid :eek: lmao. someone needs to put the koolade back in the cabinet!! :D

[hoot]

Is tow/haul dangerous when driving in reverse with four wheel steering and anti-lock brakes on ice?

[bluenote]

Scott, go to

http://www.rv.net/forums/index.cfm/fuseaction/thread/CFB/1/TID/264227/DoOnePage/Yes/page/1.cfm

The thread is now four pages long, enjoy!

Colorado Kid-

You are essentially correct about the pricing. However, the Allison is only $1200 with the Silverado LT trim package, and I believe it is the same in the top one or two Sierra trim packages. That's were the $1200 figure came from.

[SDWA]

hoot,

That would depend if you have the heated rear view mirrors, rear window defroster and the relative humidity and dew point. Danger would be increased if temperatures were below zero and passenger side window is down.

Scott

[SDWA]

Ahh! smile.gif What fun that was!

I especially liked Lone Eagle's introduction of the Tow/Haul/Race mode. That got me laughing. Maybe someone should make an aftermarket gearshift selector with THAT printed on the end of it...

Also enjoyed the idea that automatics were dangerous on hills... Hmmm, never heard of anyone not being able to get an automatic back into gear (why would you take it out of gear, though... :rolleyes: ) after trying to downshift, and being stuck in neutral because you *can't* get it back into gear :eek: and coasting at exponentially increasing speeds and having no brakes because you overheated those a mile back up the hill when you realized you *couldn't* get it back into gear and... WHAM! :mad:

I have seen the after effects of that, though!

Scott

[mbrower]

Dang, I believe his cheese done slipped off his cracker! He got really out there with some of his comments. I think he needs a nice long rest before he finds himself surrounded by big fellas in white coats.
Later!
Mark

[TBC]

I used the T/H mode on most of a 3450 mile trip towing my travel trailer (32') and it worked very good. There was couple of times I forgot to turn it on for a while but never noticed much difference. What I really liked was the downhill braking and the way it shifted down and that I did not have to use much brake. It seemed to hold pretty close to the speed where I let off the brake. I also liked the solid feel to the shift. This tranny is great and I know the F*** and D**** that I passed going up 7 and 8% grades had to be wondering what that was that went by them.

[odoh]

CO Kid ~ Appreciate the comment re what the lil' Missus thinks. To wit: I purchased my truck w/a chk that was #666. When we went to DMV to register, the plate was 6U66683. The missus had a tizzy. It was just a number to me. She kept nagging me to change plates. When the insurance premium came, it was ~ you guessed it, $666. At that point, I felt behooved to change plates or SHE would sell the truck. So, today when I changed the plates, DMV told me that there were a lot of refusal/return of the 'devil' sequence number. Whew! I got to keep my truck! ~ odoh

[AKDmax]

So if driving on ice/snow covered roads is dangerous, how are we supposed to get to our igloos in the winter? :D The roads are covered in snow, ice, and a mixture 6 months of the year here. Slow down, take your time. The longer it takes to get there, the longer you get to hear that D-max puuurrrr!

[Colorado Kid]

I believe the Allison always shows as $1,200, but that is above the price of the 4L80-E. You couldn't get a 2002 CC SLT (Top level) GMC with a 6 speed or I'd have one, so you don't see the $1095 credit for taking the 6 speed listed. But in every case that I've checked, if you could choose the 6 speed or the Allison the 6 speed is $2295 cheaper, and that's why I say the Allison costs $2295 more than the 6 speed (Which is the only resonable thing to complare it too, because it's the only other trans available with the same engines).

[JLee]

While we're dealing with tow/haul type questions, I gave my truck its first real towing test last weekend - west from Denver on I-70 thru the Eisenhower Tunnel and beyond - towing my 5th wheel. It's not too heavy, about 7500lbs I suppose. Everything worked as you all describe. My question - how long can/should one allow the engine to be in the cross-hatch (I think you call it) redline area? Going down the several 7% grades with tow/haul on I found the engine running around 3200/3300rpm at times when it downshifted. I'd just let it gradually slow back down, but I was running that rpm range for several minutes at a time. Any problem?

Like several other folks have mentioned, I found it better to run with tow/haul off except when running down the steeper grades.

Hey Colorado Kid - how goes it? Still haven't bought those Lucerix' yet, but thanks for letting me look at yours.

Jim

[hoot]

Don't forget you have brakes. Grade braking wasn't meant to do all your braking. As far as I know, this truck will not allow itself to over-rev in a grade braking situation. I believe it will upshift if the r's get too high.

Anybody know anything different?

[JLee]

Ahhh Yes - that "other" pedal :D I've noticed that I have to be very careful with the brake pedal or it'll just shift down yet another notch. Not complaining, I can always live with too much braking on those steep grades. I suspect I notice the braking more than some folks because my rig isn't very heavy.

Jim