The Duramax gremlin is back-UPDATE.

[bethandkevin]

Last year about this time I posted about my cooling system problem with my 08' Duramax. It's back. Apparently it only rears it's ugliness in cold weather. Prior to this year, I have never felt the need to plug in the block heater. I always remote start the truck in the barn and it runs one cycle (10 minutes) and sometimes I start it a second time. With my Edge programmer, I can see the actual engine temperature when I get in. It is usually 75 degrees when very cold (-15 this morning) to 120* when warmer out. On my drive to work, the temperature will climb to about 150* and then fall off until I have no heat. At some point shortly after, it will climb again, usually I don't have heat yet though. If it's really acting up, it will go over 200* and heat will return. If it doesn't climb higher than 210*, it will act normally for the rest of the drive cycle and the rest of the day if I don't let it cool completely. If it goes over 210*, it blows coolant out the surge tank overflow. I have put three sets of thermostats in it and pulled it down for a water pump to check for a spun impeller. This was not he case, so I put the old pump back on.(wish I hadn't cheaped out and put the new $250.00 pump on). All was fine after the water pump non-repair until this year when it turned cold and my gremlin returned.
This is where I ask for advice. I'm out of warranty and unable to do any major repair myself at this time due to a lack of good heat in my barn to overcome sub-zero temps. I've called four local shops that I deal with at work. One dealer is sure I have a bad head gasket or a cracked head allowing exhaust gasses to build an air bubble in the cooling system. I've checked several times with a block tester and found no such gasses. Another says clean the radiator face of debris between the radiator and intercooler. I don't think he heard me say I have NO heat, not an overheat. The third dealer, a friend works there and said don't take it there-the diesel tech has too many comebacks. So I called an independent diesel garage. He suggested the injector tubes could be leaking causing the problem. When I checked the GM repair information site, I could find no such reference to injector tubes on my year-only prior years.
So back to dealer one. I asked if I was guaranteed the repair ($6500.00) would correct my problem. He said yes....as long as I remove my programmer. He feels the programmer is ramping up fuel pressure enough to stretch the head bolts causing the head gasket issue. My programmer has seven settings. I run it on two normally as it offers the best fuel mileage.
So, to all you Duramax owners out here; Have you had a problem like this? Have you had repairs like this? If you've had a problem, did you run a programmer? If so, did the shop require you to remove it to guaranty the job?
Thanks for any experience you can offer.

TomS, I'm hoping to hear from you on this-it seems you have some GM experience yourself.

Got the dreaded call this afternoon. Problem is on the right bank in the third and fifth cylinder area. Shop said it was affecting injector performance as well on those cylinders. Vinnie gets dropped off for surgery Tuesday morning. Estimate for head gaskets (assuming he doesn't find the problem on the way that far in) $3600. That's $900 less than quoted by the dealer that I thought I had a good relationship with. If a head or heads are cracked, more money of course. The good news-my tuner will not void or preclude me from a warranty on the repair. Shop owner states he doesn't think it has anything to do with running a tuner/programmer. Just "lucky" I guess.Oh I almost forgot, shop owner let me take the truck based on my word I would bring it back without a diagnostic charge. Unheard of in this day and age!

[sambam]

I am on my 2nd Duramax and haven't any experience like this. You probably know of this site, dieselplace.com. Lots of knowledgeable guys and it's predominately D'max's. They've helped me in the past. Certainly worth a look before dropping all that money (especially if you have to leave your Edge out).

[bigskyjimmy]

Also Kevin try www.duramaxforum.com they have been a big help to me too

[hickory]

I had the same issue with a gas engine after replacing a leaking radiator. The fix was simple. I hadn't gotten all the air out of the system. Take the cap off of the radiator and run the engine until the coolant is circulating well. This will purge the air. Refill the radiator with coolant and you should be good to go. Please use caution. Do not remove a hot radiator cap! Good Luck!
P.S. Have the heater on while purging the air.

[tweber502]

There is no radiator cap on these Duramax engines unless the engines newer than the LLY in my truck have one.. There is only a cap on the antifreeze reservoir which is not pressurized. You may be able to have a cooling system flush performed which would remove any air in the system if that is what is causing the problem. Tim

[Tom S.]

Kevin, try copying your post and posting it on http://www.dieselplace.com/forum/?. Despite the forum name, they are Duramax oriented.

Unless you are noticing oil, fuel or bubbles in the coolant I wouldn't be thinking the head gaskets are bad or injectors for that matter. When you refilled the coolant after changing the thermostats, did you burb the system by opening the bleeders? Also, you said "sets of thermostats", so I'm assuming you changed both.

By chance, is your fan running? Diesels run cold to begin with, and if your fan is engaging, especially in this cold weather, it could be dragging the temps back down. We drove home in the storm last Sunday from North Carolina and I had to take my truck to the quarter car wash to wash all the snow and ice out of the radiator - it was keeping the truck from heating up too.

A word about the programmer: most places, dealers especially, will not guaranty work done if a programmer is present. The reason is they have no control on how it is used or how a person drives with one installed. In most cases, GM will void their warranty if they find out a programmer has been used. There used to be a few dealers who went so far as selling them, and still honoring the GM factory warranty, but if GM corporate finds out about it, they will void the warranty and refuse to pay for repairs. In addition, dealers were told if they were caught selling or promoting programmers, they risked losing their dealership.

[steelpony5555]

When running a programmer head bolts is another thing that needs to be upgraded too. I know that is a problem in Dodges so I reckon Chevy's can't be too different...

[bethandkevin]

Tom, it's going to a place called Cooks Diesel in Swartz Creek Monday morning. For $150.00 he says he can diagnose it. I talked to him today at lunch. I rad the stretched head bolt theory by him-he said he doubts it. He thinks its a coolant flow issuse-as have I from the start. They used to have a place near you. moved up here to be nearer to their main fleet customers. He says he has a personal friend who is a GM-Duramax engineer and that they bounce stuff off each other all the time. Impressed with the shop. Very clean and bright. 12 bays plus a triple drive through lane. Not your stereotypical looking mechanic. Very neat looking place.
No problem at all with the truck today-was too warm I'm guessing. I asked him if his warranty would be voided by the use of the programmer-he said he could tell the truck wasn't used for racing and such and if tear down was required, he could tell if the problem were programmer caused. So at this point, the programmer stays.
I'm not hearing the fan clutch locking up. That jet engine sound I know when towing in hot temps. Also, I have the cover on.
I'm confidant i got all the air out of the system with the thermostat replacement.
i surfed dieselplace today-found nothing like my situation. Duramax forum tonight.

[Tom S.]

quote:Originally posted by steelpony5555

When running a programmer head bolts is another thing that needs to be upgraded too. I know that is a problem in Dodges so I reckon Chevy's can't be too different...

That's only true if you get crazy with the tune. If you stay within certain limits, stock bolts are fine. At least for the Duramax engine.

[sambam]

quote:Originally posted by Tom S.

That's only true if you get crazy with the tune. If you stay within certain limits, stock bolts are fine. At least for the Duramax engine.

That's true in my experience. I had the Edge with 5 power levels on my '04 3/4 ton. This was 7-8 years ago. I was on the dieselplace website all the time and never even heard of replacing head bolts. The Edge was a major player at the time. I don't know about now in the post-DPF world.

[Tom S.]

Any word yet Kevin?

[steelpony5555]

My son did sled pulls on the East coast for awhile with a 2009 Dodge 2500. Talking with those guys, yes you only really need the head bolts if you bump it up above 100 hp. If you stay at the RV level tune, 50-60 or less hp, then you should be ok. Even then you only need them if you consistantly run your truck at those higher horse power ranges. Over time they will stretch with the pressures that motor will build.

[bethandkevin]

quote:Originally posted by Tom S.

Any word yet Kevin?

Still waiting for a call.