Durmax Failure

[GARY PAGE]

Had my tires rotated and balanced today at the GMC truck center. I saw a said sight; it was a 2003 Durmax 3500 with heads off. I asked why and the mechanics said the owner was very unhappy as well. Apparently valves had failed requiring a massive rebuild of the engine. Kind of make you wonder?

[GARY PAGE]

Well had to go back this afternoon due to a failed valve stem. I asked some more questions and the shop man said they had averaged 4 per month due to valve issues. I don't know what the problem really is but his advise was to stay away from the Durmax? I looked at the AL heads and they did look like a toy....

[markrinker]

It would be interesting to know what this truck was used for. My local Chevrolet mechanic is frustrated with Duramax buyers "upgrading to oversized tires and power chips" and expecting the drivetrain lifespan to be the same as stock.

Over the years, I have seen lots of premature wear on suspension, steering and driveline caused by oversized tires without proper gearing.

It seems plausible to me that four guys per month in close proximity to your dealership are hauling heavy loads and have 'turned up' their Duramax with power chips, non-standard tire sizes, etc. and are taxing the valvetrain as a result.

Also, in my back yard, contractors are using their Duramax and Power Strokes for towing that should be done with a single axle dump truck. They are breaking the law, and eventually, will be breaking their truck and looking for warranty relief!

[Kennedy]

Yeah, I was thinking of selling my Duramax due to their unreliable nature :rolleyes:

I've only got 56k on mine and already had to change the belt tensioner! :eek: Not to mention the lack of power... :(


Here you see a 5.3 gasser 1/2 ton (my next truck ;) ) pushing me up a hill with my load:


http://www.kennedydiesel.com/photogal/images/John%20Kennady%20copy2.jpg


Oh wait, that's right, he was flooring his go pedal to KEEP PACE up the hill for mph acquisition...

[Scooby]

John- what's with the black smoke ???
When I think DIESEL, I think 500,000 + without going into the motor. I am used to big trucks though, and maybe that is expecting too much of these little diesels. I have been happy with my 6.5 since the dealership put a new pump on it 4 months ago. I had had the truck 2 weeks at that time. I dont know how the Cummins or IH motors do over the long haul, but I must say GM has not been able to put out a small diesel that really holds up well. GM is all I own, and I hate admitting their flaws.
I may begin towing with my truck in a few months, so I will be calling Kennedy for an exhaust and computer upgrades. I hope it holds together.

[Shad]

I don't think you can look at not buying something because you see one broke in the service shop. Just about every vehicle make has a few bad eggs. Just hope yours was not made on friday at closing time... "AAHH! looks good enough"...That's just a little humor, I know a guy who worked for AMC in Kenosha who has a few stories.

[Dvldog 8793]

Howdy
I think it really depends on who you talk to. A service shop is going to tell you about lots of horror stories because that's what they see. About a year ago I think I remember a new member asking what the deal was with the 6.5? Judging by this board all we have are problems and not enough power. It must be the most unreliable wimpy motor ever made! :D Well, that's what this board is about, helping people that do have problems with the 6.5. There are ALLOT of 6.5s out there that have never been touched! And then there are the guys like me that can't leave good enough alone! :D tongue.gif MORE POWER and all that!
I guess what I'm getting at is that there are MANY Dmax's out there that have a ton of miles on them with NO problems. My neighboor owns a salvage yard and he has two of them with 200,000 plus on each one! I don't think he has ever had a problem with either. His maintenance ain't the best and most of his loads are hauled late at night if you get my drift! ;)
L8r
Conley

[markrinker]

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2460245976&category=6729&sspagename=STRK%3AMEBBI%3AIT&rd=1

Here is a 266,000 mile Duramax. The seller claims that it has only had an alternator, batteries, hoses and belts! If it were 4WD, I'd buy it for the $12,500 reserve price.

[Kidd]

Good heavens, I surely hope all Duramaxes don't smoke like that, haven't seen the like since the last tractor pull I attended. Mind you, those diesels were cranking out about 1400 HP. :D
Probably John Kennedy is closing in on that.. :cool:
K.D.

[d.h.]

If you look at John,n h/p# he,s putting down some real power.That would explain a lot of that smoke.I think its great :D

[C.K. Piquup]

My`95 smokes like that.It`s a sign of life!I think that dealer mechanic was exagerating.He`s probably divorced,paying child support on 5 kids,lost the house,living with Mom,drivin`a 3-tone`76 Datsun,hittin`happy hour at the strip-club daily,needs 6 root canals,and just ressents the fact that these folks are able to afford these trucks.I know that`s true in my case.A little humor here.

[More Power]

If the Duramax was having routine cylinder head problems, you'd see it all over the net - especially BB forums. People are not shy about posting the problems they're having........

The fact is - the aluminum heads are a big contributing factor in the success of the Duramax. Watching one run at more than 1500 degrees EGT for two miles (loaded hill climb) will convince most skeptics of the heat dissipation ability offered by aluminum. That event happened nearly two years ago, and the engine is still going strong.

MP

[Kennedy]

I guess that smoke was at the start line, and a bit of turbo lag played in.

I purchased a core Dmax with a dropped valve, but that has been a rare occurrence.

Looked to me like the tip of the stem snapped off inside the rocker bridge as the end of the stem was polished and worn round. Curiously enough, the next cylinder in line had a valve with a visibly shorter stem. Not sure what happened, but there is no longer a piston in the hole with the bad valve, only a wrist pin and a LOT of grooves...

[HANK1948]

black smoke, that means power baby! puttin the coals to her! watchin modified diesel truck and tractor pulls without the smoke would be preaty boring! :D

[CaseyR]

John -
What's the story on the very high replacement cost for injectors on the Dmax? There was a post sometime back saying that replacing them was several K just for parts. Lost track of the thread, however.

[C.K. Piquup]

Injectors or injector system,I wunder.The hi-pressure rail system is state-of-the-art and I`m sure quite a salty piece o`meat.I don`t know,but sure hope replacing injectors wouldn`t cost several K to buy.What am I saying?Yes I do,that means people will be dumping DuraMaxes right and left in several years and we`ll be able to gettum cheap.