6.5 Disaster

[DayRadebaugh]

I'm a former member who has a history with GM diesels. Had a '99 Diesel suburban that required a new injection pump, done under warranty. Sold that suburban, bought another '99 diesel Suburban with better options. Love that vehicle, I keep it pristine, but also can't keep it running. When problems began, car had 59K miles, now has 62K.

Here's the story:

1. At 59K miles, in May '12, engine running rough, threw a P1218 code, took it to Briggs Motors (Chev dealer, Manhattan, KS). They replaced injection pump with new injection pump and harness, approx. $1,000. As I remember discussion, I wanted to keep vehicle original, but they put in an injection pump that required removal of the big gray plastic shroud that sits between the cylinder banks and presumably covers the pump. My impression is that this pump was not exactly stock, but something aftermarket they felt was an improvement.

2. Didn't drive vehicle much (about 300 mi) over the course of the next year, but in June '13 (1 yr+1 month later) the replaced injection pump croaked, and they replaced it w/o charge for the pump, but i paid the labor (approx. $500).

3. Still wouldn't run right, so they dropped the tank and drained the fuel ($400).

4. In July '14, 62K miles, car won't start. Diagnosis is failure of lift pump, which caused injection pump also to fail. Estimated cost to repair approx. $2,800.

I am constantly told by the dealership that these vehicles need to be driven, and driven hard, and this is the source of the problems. However, I have driven it 3,000 miles in the last year; i keep vehicle for long trips, not commuting, and don't tow with it--I have an '04 Duramax 3500 pickup for that.

I love the car, but am disgusted with such a vehicle. Nowhere can I find GM claiming that you have to drive these things all the time to keep them reliable. I have 3 other diesels that I drive infrequently, but are reliable. These are a '95 MB E300 diesel, and 1980 Autocar with a 290 Cummins, and a '63 Mack with a 237. I'm suspicious of this claim that they have to be driven all the time.

Even though I want to keep the Suburban, I have no confidence that this sequence of events won't happen again. What can I do?

Would appreciate some advice. Options, as I see them, are as follows:

1. Are these 6.5 injection systems simply junk, and I should give up?
2. Should I convert the vehicle to a Dura Burb?
3. My current plan is to collect the facts (I have all the invoices) and sue the dealer and General Motors in small claims court. Who can tolerate a vehicle that requires $1,000+ investment whenever you try to drive it?
4.I restore old trucks (see attached pic of some of my fleet) and am prepared to replace these pumps rather than turn it over to a dealer again. Can the advanced amateur accomplish this? I have all manuals needed to do this. I assume you have to R&R the units, purge system, and retime injection pump
Would appreciate any ideas you have.

Help--any suggestions appreciated. Thanks

[sctrailrider]

My suggestion would be to convert to a manual injection pump ( DB2) .. they are very reliable and not too much to convert.... there is a very good write up on everything to do when converting to a manual pump if needed... lots of folks have done it .....

[DayRadebaugh]

excellent; thanks for the suggestion. this whole business has been so badly screwed up--perhaps--by the dealer that i wouldn't mind doing it myself.

any references on this manual pump?

[ToddMeister]

My 95 GMC 6.5 only gets about 6000 miles per year, mostly commuter miles. The injector pump has never been replaced by me, not sure if it is the original pump or not.

But the PMD (black box on the side is another story. I bought the PMD heat sink, a new PMD and extension cable, then mounted PMD/heat sink in front of the driver's side battery and connected the extension cable. I've had no trouble with this system since it has been installed. The PMD on the pump developed issues causing stalling.

The dealer removed the engine cover on your truck to attempt prolonging the PMD's life. But the PMD driver still gets heat soaked every engine thermal cycle.

Either go with the new PMD/heat sink, or convert to a mechanical DB2 pump as suggested above.

Also look at adding a relay to the lift pump circuit. This powers the lift pump through a separate higher power relay contact, and the oil pressure switch just powers the relay coil, which improves reliability of the lift pump circuit greatly. I have also done this mod to my 95 with good results.

These engines don't have to be driven hard all the time, that is dealer BS. It doesn't hurt to open them up once in a while, though. Good luck.

[sctrailrider]

Go here , click the first one and download it and save it...

I haven't done the swap myself, but others say it isn't bad at all and very worth it to be rid of the DS4 pump....

[Yukon6.2]

Hi Day
Don't go back to the place that worked on your Suburban,they just use your wallet for their own use.
If you decide to convert to mechanical PM me you email addy and i can send you some pic's of the conversion that i just did on my 98 K3500.
You will need to do a little fabrication to make a bracket and adapter for the throttle linkage,and high idle solenoid.
You will need a few parts and pieces,the biggest hurdle you will have is controlling the tranny.
Most of the time the electronic pumps are fine,but once someone gets working on them if they don't know them problems can develop.
In my case I'm in the middle of nowhere and can be out in my truck at -40F without any cell service on a towcall . I lost confidence in the truck and would always wonder if i would get home.My truck dosn't get driven daily and i went through 4 PMD/FSD's 1 optical sensor,and 1 ignition switch in less than 5000 miles.
Now i don't have the same worries.The truck starts great now,didn't before always had a smoky start.
Thomas

[trbankii]

I am lucky to put 5000 miles a year on mine, but do drive it at least weekly. Certainly not driven hard - some towing here and there but mostly just for household and workshop supplies in the bed. The biggest issue I've had has been with the batteries draining - no fuel issues. I do dump PowerService Diesel Fuel Supplement +Cetane Boost into it with each fill-up. Between the low sulfur and questionable quality of our fuel supply, it seems like cheap insurance. Mine is a mechanical pump OEM.

[arveetek]

First off, I'm sorry you're having these troubles. My immediate suggestion is to please forget trying to sue the dealer and GM. GM is going to be absolutely no help on a vehicle that is now 15 years old. The dealer is probably trying to do the very best they can, but most dealers are not properly equipped or trained on this engine to do diagnostics. The only thing you'll accomplish by trying to sue somebody is making some lawyers richer, yourself poorer, and a lot of hard working families very upset.

Secondly, these 6.5L fuel systems aren't really that bad, but have a few quirks. Most of the time, as mentioned, it's the PMD/FSD that is the culprit of failure, but most dealers are required by Stanadyne to replace the entire injection pump if that is the case. However, you can purchase a remote-mounted FSD and FSD cooler and install it yourself. It's not hard to do at all.

I would try looking for a competent 6.5L diesel mechanic in your area who can help you through this situation.

Good luck!

Casey

[DayRadebaugh]

First off, thanks very much for the suggestions; these are very helpful indeed. A few responses:

First, I remember discussions about heat sinks, and the dealer did install a new "harness" in the process of fixing the injection pump. This sounds very much like the PMD that was mentioned.

Secondly, appreciate the reaction to the claim that I have to drive this frequently to maintain reliability. It's dealer BS, pure and simple.

I'm still going to go after the dealer for some compensation, but have convinced myself that I can install the manual pump with some guidance. I did, after all, change out a blown diesel on my '63 Mack B81 SX with a rebuilt 237.

I don't want to give up on the vehicle; it has all I want, low miles, and I would assume that if you fix the fuel and electronic problems one way or another, the engine itself will go forever.

By the way, has anyone ever done a Dura Burb?

Grateful for the advice,

Day Radebaugh

[DieselDavy]

Chris,
I'd like to download the DB2 files, but for some reason, I can't get to them. I even opened an account so I could "see" them (I hoped). No luck.
Could you post the files or email them to me?
Thanks,
Dave

[trbankii]

I can download without be logged in. When you click on the link, can you at least see the three files? The two pictures are just the cover to the document and "no DS4" "sticker" that you could print out and use. But the document is 17MB - a bit larger than you could just email.

By chance, do you have any pop-up or advertising blockers running?

[DayRadebaugh]

Guys:

Does the dealer's explanation that the failure of the lift pump in turn caused the injection pump to fail sound plausible at all?

[arveetek]

Guys:

Does the dealer's explanation that the failure of the lift pump in turn caused the injection pump to fail sound plausible at all?

Yes. The injection pump (IP) can pull fuel from the tank on its own, but is not recommended. Plus, the lift pump is designed to not only pull fuel from the tank and push it through the fuel filter into the IP, but also to recirculate fuel back into the tank. This keeps a steady supply of fuel going to the IP and back to the tank, with the idea that the fuel will help cool the IP. This is especially important if the FSD is still mounted to the IP. The fuel is supposed to cool the IP and FSD.

Long-term use of a failed lift pump can cause premature wear and tear on the IP, and cause the FSD to fail quicker.

Casey

[DayRadebaugh]

thanks for that explanation. by the way, i was able to download the db2 documentation. i intend to give it a good read, and hope to be able to do this conversion in the wintertime.

does anyone know of a good 6.5 mechanic in the wichita area, if i get into a fix?

[DayRadebaugh]

Chris/anyone:

I've studied the DB2 conversion document. It's an ambitious project, but I think I could do it. I have a few questions.

Do you know who wrote it, in case I needed to ask questions?

My burb is a '99; would these instructions apply as well to this later vehicle? The introduction to the document mentions that the instructions are for earlier pre-OBD II vehicles.

Do you know anyone who would perform this conversion for me, if I were to ship the vehicle to them?

Any suggestions about how to find a good 6.5 mechanic in the Kansas area?

By the way, I don't know if anyone has experience with DuraBurb. This option looks quite attractive, but I've contacted them by email and phone, with no luck.

thanks for your help.

Day Radebaugh

[sctrailrider]

I have not done the swap ....

You could contact member "chevydiesel" , he is in TX, he might have time to do the swap, I'm almost sure he has done it...and could maybe do it for ya...

[DayRadebaugh]

Thanks Chris

Day

[DayRadebaugh]

Chris:

couldn't find chevydiesel. in fact, TDP only lists 13 members. can we PM? I'm Day Radebaugh at dayradebaugh@hotmail.com, 316-323-9432.

thanks

[sctrailrider]

Chris:

couldn't find chevydiesel. in fact, TDP only lists 13 members. can we PM? I'm Day Radebaugh at dayradebaugh@hotmail.com, 316-323-9432.

thanks

sent ya a email with the contact info....

[phantom309]

I personally wouldn't convert a pristine low mile burb to a mechanical pump,.

If you have an aftermarket pmd mounted on a cooler in the front nostril of the bumper it makes these 6.5's pretty reliable,.

If i were you i would read this forum for a couple of months in your spare time,. and read about the "list" of upgrades most folks do over time,.

knowing what i know now and if i was lucky enough to find a nice low mile suburban, (a 95 would be my holy grail)
I would do these mods,.
1..remote mount pmd almost immediately.
2.. better exhaust including better downpipe.
3..add the better water pump with the 4 corner cooling mod single stat (very touchy subject on this forum)
4,. OPS relay running a better lift pump,
5.. remove the in tank sock and install an inline filter before the lift pump,.
6.. Upgrade the factory glow plug harness and use the duraterm glow plugs
7..install head studs,.
8. install an aftermarket turbo (touchy subject on this forum)
9,.upgrade the ecm with a better chip (programming on OBD2 trucks)
10 add a shift improver kit to the trans with bigger cooler,.
11.. add the pyro boost and trans temp guages,.

Having said all that, if you have the budget to do a duramax/allison swap,.

well thats kinda the ultimate upgrade,.