Question: how common are head gasket problems?

tobyk321

BIODIESEL BURNER
Jun 23, 2007
464
0
16
41
milford, nj
www.myspace.com
OK guys i need some help here. i tunned a friends 05' lly, i put in Pat's 20/20 tow tune. he only wanted a little more power and better mileage. the truck was fairly neglected, when they changed his trans oil it came out black :eek: , and the guy doesn't really keep up on maintenance. now one of his head gaskets is blown. what I'm really looking for is a little reassurance that my tune didn't cause this and it is a common problem on lly's. also he wants to know about how much it would cost him to replace them? thanks for the input.
 

tobyk321

BIODIESEL BURNER
Jun 23, 2007
464
0
16
41
milford, nj
www.myspace.com
yes it is a high mileage truck 117,000. I'm thinking his poor maintenance might have something to with it. i don't think that small of a tune could cause it, but it does have me worried.
 

NelsonDiesel

Formerly StewieTuned
May 8, 2008
896
0
0
41
Buena Park, CA
www.NelsonDiesel.com
yes it is a high mileage truck 117,000. I'm thinking his poor maintenance might have something to with it. i don't think that small of a tune could cause it, but it does have me worried.

i'd feel the same way too.

But, realistically it wasn't caused by you.

Head gaskets will be expensive. dexcool does not have a good reputation and if it is still original coolant.... also, an accidental ingestion of gasoline in the diesel fuel system can cause major heat issues in the cylinder....
 

TxChristopher

Sometimes Helpful
Feb 8, 2007
70
0
0
Unlikely it was your tuning, head gaskets blowing is common in the LLY. The LLY swings temperature so fast it promotes head gasket failures, the aluminum and cast iron expand and contract at such different rates that the gasket has no chance.
 

SFC Cobb

New member
Oct 22, 2008
76
0
0
83
Hurst, TX
I had one on the right side start leaking down the side of the block at about 150K and got back by adding GM stop leak. Had it changed at about 230K.

I just had both head gaskets replaced because of white smoke that was not caused by injectors. They pulled it down to the block and the left gasket was leaking into #6 cyl. $5269.64 later I have it back. $3500 labor (35 hrs @ $100per hr) and $1300 in parts.

They must have done a lot of cleaning up of intake etc because just a little punch of the throttle jumps the boost up to 20 psi really fast. Haven't seen that in a long time. You get used to driving it and they change gradually without realizing it changed.
 

Killerbee

Got Honey?
I would suggest "wastegate" tuning.

Over-advance is surely contributing to any head gasket failure. Dynamic timing retard is the safety net. The LLY has some pretty crappy stock tables. Unfortunately, most tuners don't have a clue what to do with them, tables like IAT Boost, ECT timing, etc.
 

SFC Cobb

New member
Oct 22, 2008
76
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83
Hurst, TX
Looks like mine are gone again at 41K - starting to get aggravated. ONLY 10K or so since they were just done.:mad:

Unless you have a lot of boost you should not be having problems like this. The dealership must be doing something wrong. Try a different dealership service dept.
 

durallymax

New member
Apr 26, 2008
2,756
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Under The Hood
Next time you tune somebodies truck even if it isnt yours and they are your best friend have them sign a waiver anyways that way if they try blaming you you are not at fault.

But I doubt your tuning caused this. After 17 hooks to the sled, some brakestands, 20-25s in limp mode and plenty of pounding my trans fluid still came out bright red surprisingly.
 

Pondsy

New member
Jan 4, 2008
641
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53
Plymouth, MA
Unless you have a lot of boost you should not be having problems like this. The dealership must be doing something wrong. Try a different dealership service dept.

The dealership did have some issues with previous work (not the least of which was failure to torque the injectors which all came loose after head work). I'm not running much boost - most I've seen (unless guage doesn't work proeprly) is about 27-28.

That's why I don't believe it was Toby's tunig that caused that guys issues. Likely just poor maintenance that led to bigger problems starting to show up. But I don't have any facts that would back up my opinion.

As for my problems - we'll see!
 

tobyk321

BIODIESEL BURNER
Jun 23, 2007
464
0
16
41
milford, nj
www.myspace.com
well i just got off the phone with the guy and he told me that the water system had been pressurizing itself even the engine was cold for a couple months now, so it sounds to me like it had a head gasket problem for while.
 

bounder39

06 GMC 3500 LBZ Dually
Oct 18, 2009
7
0
0
Barrie Ontario Canada
Blown Head Gasket

I have an 06 GMC 3500 LBZ and it's in GM right now due to a blown head gasket. My truck was never tuned but it still blew. It's been going on three weeks that it's been there. It was 50 kilometers over the warranty limit but they said it would be covered. I went to three shops and I even stopped at a GM dealer and they all thought it was an exhaust leak. It was on the driver side at the back and when the mechanic got into it he finally realized it was blowing out the back of the head gasket. I don't know all that their doing but they stripped the whole engine on both sides. Anyone know what they might be doing because I don't. I was not even pulling a trailer when it went. I would think that your friends truck had nothing to do with the boost. Maybe they had bad gaskets like mine. Wish him luck and tell him to go after GM for the warranty.Chances are the gasket was gone before the warranty expired. Try their head office you don't have anything to lose.
 
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JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,712
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Texas!!!
I have an 06 GMC 3500 LBZ and it's in GM right now due to a blown head gasket. My truck was never tuned but it still blew. It's been going on three weeks that it's been there. It was 50 kilometers over the warranty limit but they said it would be covered. I went to three shops and I even stopped at a GM dealer and they all thought it was an exhaust leak. It was on the driver side at the back and when the mechanic got into it he finally realized it was blowing out the back of the head gasket. I don't know all that their doing but they stripped the whole engine on both sides. Anyone know what they might be doing because I don't. I was not even pulling a trailer when it went. I would think that your friends truck had nothing to do with the boost. Maybe they had bad gaskets like mine. Wish him luck and tell him to go after GM for the warranty.Chances are the gasket was gone before the warranty expired. Try their head office you don't have anything to lose.
Probably changing both head gaskets.
 

bounder39

06 GMC 3500 LBZ Dually
Oct 18, 2009
7
0
0
Barrie Ontario Canada
Thanks Have you heard about any other problems with these trucks. I heard they were bullit proof. Thats why I bought it so I wouldn't have any problems. I was thinking about boosting it up to pull my RV trailer but I don't think so now.