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Mark-
03-01-2016, 12:02
04.5 head gasket help
OK so after 150k miles and years of towing my 5th wheel with the coolant temps fluctuating between normal and 238 deg and back down, the head gaskets finally failed. So $6k later I have a new water pump and a pair of new head gaskets. The question is how long before they fail again? I'm still towing although not as often.

Are the new head gaskets improved? New head bolts stronger? Will they fail again? Has anyone here had any experiences after the gasket replacement good or bad??

Thanks,
Mark

More Power
03-01-2016, 15:25
Yes, the gaskets have gone through a few iterations since the Duramax arrived. If the gasket job was done right, it should last at least another 12 years.

Kennedy
03-02-2016, 16:19
What I can say is that I have never seen a properly done head gasket job using studs and the early or mid style gaskets repeat fail.



I have definitely seen repeat fails when bolts were used. We never use the OE bolts. I believe the bolts to be a key factor in the failures and not the gasket design. We do not use the latest gaskets from GM either. I believe they downgraded personally, changing down to a 3 layer gasket and eliminating the crimped fire ring and cutting the cost by something like 66%. It just defies logic that they would be better.

More Power
03-03-2016, 13:26
There are at least 2 types of diesel head gasket replacement environments.... 1- Typical stock power oriented. 2- Performance oriented.

The typical stock power head gasket replacements are expected to run for years... Not many expect a performance built engine to run as long before it needs help. After all, the 04.5 head gaskets mentioned earlier did provide service for 12 years and 150K miles.

I wonder if the very newest Duramax engines are using the very newest replacement gaskets and Torque-to-Yield head bolts? I'd think GM would want to reduce their warranty exposure.

Kennedy
03-04-2016, 08:39
The vast majority of our head gasket jobs are on stock street trucks. I do however have a fair number of race and HP applications running as well. The HP applications simply test the process even further. I can honestly say that we have never had any of these fail with this process. We never worried about the crimped versus riveted gaskets in fact the crimped ones were all that was available in the OS/OB gaskets for quite some time. I think that GM misidentified the lack of clamping force allowing movement as suspected layer shift which of course proved not to be the case.

When GM changed to the new 3 layer gasket I looked at it puzzled. I took it to my machinist and we both agreed that we did not like the looks of it.

My feeling is that GM looked at the fact that the fire ring/wrap was splitting and decided that like Ford they didn't need it. We know how well that worked for Ford...


Note: High boost applications like my 2002 that runs in excess of 80 psi we embed a stainless wire ring with a very slight protrusion that engages the fire ring. We also use super grade studs or larger diameter studs.

Mark-
03-04-2016, 11:10
So after paying the chevy dealer to do the job back in July, you're saying that they will fail again? And how long will a dealer job last?

Kennedy
03-04-2016, 11:30
It's hard to say. Back together the same way it came is the same crap shoot you take driving it off the lot. May never give grief again, but Chessy just had his done for the second time after using bolts the first time.

Mark-
03-05-2016, 10:19
Crying shame. So I have done everything to my LLY that has been recommended in these forums with exception of a new larger radiator to no avail to keep the temps down. As a retired diesel truck mechanic I am sure that the constant high temp fluctuations when towing is the main cause for the original head bolts to stretch and lead to an eventual head gasket failure.

And to find that the flat rate time to replace the gaskets, plus bolts etc was in excess of $5900, makes owning an LLY extravagantly expensive. After all, many of us buy their diesel for the fuel economy, power, AND Longevity...

So now that I am retired, on a fixed income, I am not only punished with $6k worth of repairs, but am faced with a similar result in the future...

Shame on Chevrolet! So do I sell off my LLY and find another truck for my RV or take a shot on this dealer repair with genuine GM parts lasting?........

rapidoxidationman
03-05-2016, 17:38
If you have the tools, the gaskets aren't that hard to replace yourself. I did mine and haven't ever been into a diesel top end (or bottom end, for that matter) before. Lots of pictures, AlldataDIY.com, and a borrowed flywheel locking tool and air hammer to break the camshaft pully loose. Had the heads cleaned, surfaced, and new valve guides installed at a machine shop ($700?), installed ARP head studs and miscellaneous parts courtesy of Kennedy diesel, did the water pump since I was in there, and had to replace a valve cover because one of the injectors was NOT coming out gracefully ($100). All in with gaskets, fluid, miscellaneous bits was well under $3k, closer to $2500.

I learned how to do this because there was no damn way I could stomach paying Chevy $5500 to do the gaskets only using OEM parts (bolts) and no upgrades to the heads and no water pump.

Edit: I also borrowed an angle sensing Snap-On torque wrench to tighten the head stud's bolts. Given what I saved over the dealer cost, I could've purchased the tool and still come out ahead and had a really nice torque wrench to boot.

Took me almost 60 hours - book time is about 40. I think I did alright. It was about 70K miles ago.

Kennedy
03-07-2016, 07:50
My 2005 left to friends of the family with 98k on the clock. It is running fine completely stock. I don't think it gets a lot of regular use, but it does tow back and forth to AK annually.

My 2002 had original head gaskets in it when I finally popped a piston/rod from running too much HP/nitrous and 750+ HP.


I'm the kind of guy that likes to put things back better than original (within reason) and for several hundred dollars against a several thousand dollar project, I have no trouble justifying the expense.

SoTxPollock
03-07-2016, 14:41
Alright you guys are causing me to be concerned. I also tow heavy trailer a few times a year, but the only time I saw water temps like that was coming out of death valley, outside temp was 126 so I figured 100 or so more for water pulling that hard wasn't too bad. I haven't experienced a head gasket failure with 233,000 miles on my 02, but I watch my gauges pretty close.

1. What was your first clue the head gasket was failing, was it something slow or did it just all happen at once? Just curious in case I start to experience the same event.

Kennedy you are right on the money. The wire ring and studs would be my obvious choice.
What kind of torque numbers did you use to hold em in place since GM's twist to partial distruction doesn't tell me much about how much torque is generated when you torque bolts the "new" way now?

Mark-
03-08-2016, 10:00
So there is no manufacturer that anyone knows about that makes a replacement radiator that is larger for the 04.5 LLY? I know the V2 is no longer available.... So other than some cobbled up set of spare radiator parts, we're basically screwed?

Kennedy
03-08-2016, 14:24
cooler towing dot com picked up where TxChristopher left off.

Mark-
03-09-2016, 11:01
Thanks for that info