04 gm duramax oil consumption/loss mileage

[mrcrsr]

everyone should see the post in the lounge, 04 DURAMAX LOSS OF MILEAGE, and see what a gm employee had to say, and let this info weigh on you when it comes time to purchase a vehicle

[Bill Schwab]

Our entire fleet switched to GM DuraMax after I dumped the last Ford truck we'll ever own last year. Thus far, 12 trucks, ranging from 3500 4x4's to 6500's with a 475 cubic inch DuraMax and a 9 speed tranny. Milages range from 9,000 to 150K, and not one single issue. The 6500 is getting 14 MPG empty, 11 MPG hauling 7 tons or a trailer with a Cat on it.

You must have a fluke.

[Ted Stryker]

The equipment & tent rental store next to my electrical shop has had 3 Duramax's all 3500's, and they all look like there burning pine knots all the time... Nothing but BS out of those trucks for the rental people... One of my long time buddies was an ASE Mechanic for our largest Chevrolet dealership ( Red River Chevrolet )in town, and He has not one good thing to say about those engines... He say's that they are Boomarang engines, meaning that they may leave the dealership but they'll be back... But like Mr, Schwab mentioned, I sure there are some customers that have had great service with them... I'm only saying that in my corner of the globe, they have been very problematic engines... Let it be said that I have never owned one myself, I know only what I have heard and seen but no first hand experiance...

[venom280]

I Love My Duramax, Will Never Own Another Powerstroke Or Cummins

[mrcrsr]

gm sucks and should go out of business, with there customer service being what it is

[Bill Schwab]

One thing that is documented. The early Dmax engines had injection problems. After doing a project at the home of a senior engineer on the Dmax/GM project last year,(coincidence) I got alot of history that not to many others could get. Originally, the Dmax engine was going to use the Nipondenso injection that Isuzu designed for it. (Gm owns 25% of Isuzu after they could not pay off a loan from GM in the 80's)

So as the project goes forward, GM interviews Isuzu and Caterpillar for the new engine to replace that garbage 395 cubic inch turbo diesel it had been using. The whole time they had a relationship with Robert Bosch who was supposed to get the injector/ injection pump sale to whatever was decided they were going to use.

GM signs with Isuzu, and tells them they are going to use the engine, but, Isuzu was to retrofit the Bosch system to it's engines. That system relies largely on the use of vaccum from the tank fed by a push pump inline, and a mechanical pull type pump to feed the injection pump. The flaws are as you well know, if you ever develope a vaccum leak in those lines you can hunt that thing down for weeks and not find it.
The only other things in the early Dmax's are head gaskets, just like Ford had with the 420 cubic inch IDI cornpicker diesels it instaled in it's trucks.

The 05 Dmax's came with Nipondenso high pressure injectors and are flawless. I have 400,000 mile engine/tranny warranties on our fleet. Oil consumption is about a quart every 3500 miles, and we dump oils at 5K and replace with Valvoline 100% synthetic.

In contrast to the D'max engines, Ford came out with it's illustrious 366 cubic inch PSD, or the downstroked stroke.
Commonly replaced parts are turbos and transmissions. They have had 12,000 consumer complaints since 2004, accompanied by 77 service bullitens regarding thate engine. There have been 500 injector parts changes since it first came out. Then you have Ford's better idea...Some freeken genious designed the tranny so it does not flow oil in reverse gear. I have had to shuttle my friends back quite a bit when we are out in the dessert when in thier Ford takes a dump and we run a pool on when and what the next part to break will be.

In our area, where 6°-10° grades are common in the Sierra Nevada mountain range, we pull heavy loads, and, we have to back up alot. So, you put your foot into it to go back, place the truck in park, set the brake. Unhook your load (trailer) or dump your load, put the truck in gear and the oil inside has cooked, expanded and pushed the front seal out of its carrier. When you place the truck in drive, you proceed to pump all the fluid on the ground and fry the pump. Cost of rebuild, Cha Ching...$2,100-$2,500.00

Thus, never again a Ford in our fleet. 3/4 of the job weather it work or play is getting there and back. It appears that when Ford made the new stroke, they made something similar to the OMC 90HP V-4's that would drop to an idle in a left turn, or like Merc had when they made the 110, famous for rods going and pistons sticking. Both engines were junk.

Now if you are on flat ground, these issues exist, but they will not be the killers they were for us here in San Diego. When I had my company in Illinois, we had tranny issues plowing snow, but fewer and farther between. Anyhow, it' a fluke issue you got going on. Before I dropped the near million dollars it took to replace our fleet, I did pleanty of homework.

[marcus10]

I am a tech at a large chevrolet dealership and have to say that really the only problem that we have really seen is with the injectors leaking. I am still amazed at how good they run and how dependable they really are. All I work on is automatics and I think that the allison is one of best transmissions every sold in a one ton.

[frank owen]

I Have A 2001 Year Duarmax Diesal With A Allison Trans. Are They Having Any Problems Anyone Know's About? So Far I Have Had No Problems With It. I Only Have 46,ooo Miles On It. Thanks Frank Owen

[The Big Al]

I am a tech at a large Chevrolet dealership and have to say that really the only problem that we have really seen is with the injectors leaking. I am still amazed at how good they run and how dependable they really are. All I work on is automatics and I think that the Allison is one of best transmissions every sold in a one ton.

This is the problem with the early engines, injector seals are designed wrong, and need to be updated.

Fuel dilutes the oil, ie: cause oil use.

Need to take vehicle to medium duty truck service center and not a reg dealer.

[marcus10]

Why would you take it to a med duty dealer? We have 3 or 4 techs who love working on these and we are just a regular dealer. Even the new style injectors are having trouble though but they are lot easier to replace.

[marcus10]

I'm not trying to start an argument or anything but any more light duty techs are just as capable of working on the duramax and allison as the medium duty. The first couple of years I would have taken it to a med duty but now I wouldn't worry about. As far as an 01 the only real problems have been the injectors, which I think are still covered in the special policy warranty, and also the early valve bodies and prndl switches had some problems. other than that they are great vehicles.

[The Big Al]

Why would you take it to a med duty dealer? We have 3 or 4 techs who love working on these and we are just a regular dealer. Even the new style injectors are having trouble though but they are lot easier to replace.

The regular dealer in some cases is not up to date on the info with the Dura Max. But if the dealer has a man that specializes on Diesela then he should be up to date on Notices and programs dealing with the engine.

Personally, GM should have a recall, but that will never happen.

[marcus10]

Right now it is not really a recall but if you do have an injectors go down and they have not been replaced they are covered well after warranty. The problem with a recall is the parts they replace them with are not a whole lot better than the original. If they ever perfect a set I am sure they will probably have a recall. I have always hated everything about diesels untill the first duramax I drove, I was quite amazed at the power difference between the old 6.5. If it wasn't for the injectors I think that it would be one of best engines gm has. I have been to all the allison hands on classes through gm but I have yet to need to overhaul one. If they do happen to fail it is normally high mileage with some kind of aftermarket power tuner installed that changes the factory pressures and shift points. They still have not lowered the prices of the parts for them yet though. If it needs a converter and anything else it's cheaper to replace with a srta and get 100.000 mile warranty.

[frank owen]

Marcus, would you wait untill you have a problem with the injectors before taking it in? What would you do? And what to look for if you have problems? Thanks guy's for your help.

[marcus10]

You will know when you have a problem. It will be hard to start and smoke very bad and the oil will be full of diesel. You may never have this problem. I have seen several of these trucks with 300,000 miles and never had a problem.