I have an early '06 with low compression and my mechanic wants to rebuild the head.

So my questions are:

Did they change the heads in the latter models to improve the design and if so would they fit on my '06.

What is the part # of the replacement GM head?

Does anyone have a source of warrantied rebuilt heads?

The local ex-hummer dealer wants $3500 for the job, my mechanic is in the $2300 range and has done this before on the Colorado's. I just want to find out if I should have it rebuilt to any latter spec's than '06.


Thanks

 

if you go back to the hundreds of posts on 06 heads you will probably want a later piece of metal. not worth the gamble ,,id say

 

Here is some info i think will lead you in the right direction.
It was a softer valve seat in the early 06 models that was causing the head problems.
They have replaced them with harder valve seats and yes they will fit your h3.
So what were your compression test readings like? I have an early 06 as well and recently did an engine compression test myself and was wondering what other 06's were putting out.
Condition/Concern:
On rare occasions, a SES light and P0300 may be experienced due to a single cylinder misfire at idle that may or may not be felt. This may occur before the VIN breakpoints above due to non-uniform intake valve seat wear, which may prevent the intake valve from sealing properly. Vehicles built after these VIN breakpoints contain harder intake valve seats to address this concern. If the engine misfires occur off of idle, this PI does not apply. Bulletin 07-06-01-011 contains a labor operation and related tips for performing a cylinder leakage test to diagnose this concern but it does not indicate what repairs should be performed if a leaking intake valve is found.

Recommendation/Instructions:
If the SI diagnostics do not isolate a cause for this concern, refer to the latest version of 07-06-01-011 and the "Cylinder Leakage Test" procedure in SI to perform a cylinder leakage test. If a leaking intake valve is found, replace the cylinder head by following the latest version of 06-06-01-017, which contains the necessary replacement procedure and part numbers. If the vehicle is a 2006 model, install the latest PCM calibrations to complete the repair. The cylinder head received from GMSPO contains harder intake valve seats to address this concern.

 

Step 1. Contact 1-800-HUMMER and see if they will cover the entire head replacement. If not see if they will cover the part or the labor. Mention the GM "Good Will" programs you have been hearing about.

If step 1 does not work at all (I'm sure they will offer something) then I suggest you make sure whatever replacement head you end up installing or having installed has the newer casting and or valve seats that address the original problem.

Hope this helps!

 

If you are asking, can I put an 07+ LLR (3.7L) Cylinder head on my 06 L52 (3.5L), the answer is no. The Part Number for the L52 head is 12611423.

There are no "new" old ones with the defective valve seats available through GM, they were all pulled when they made the fix for all L52s built since March 31, 2006.

So you first need to find out the cause of your problem, no point in trying to "rebuild" the head if the valve seats are defective. If your VIN# is lower than 287591, you should buy a new head and components or try to get help from GM. You can purchase the entire assembly if you have to, but I do not have the PN handy for that.

If you have a broken or weak valve spring, you can rebuild what you already have with new springs, retainers, keys, rockers .... etc.

Call the 800 # first per above, especially if your Vin # is in the bad range.

 

I agree with the two posts before me.

 

I would look into what the parts are going to run you, and what they're talking labor wise... Part of me thinks that you might be better off on an engine swap to the 3.7L...
Doc/Taint would it be a direct swap? Or would he have to mess with the electrical as well?

 

Throw in a V8.. Good luck with what ever you do....

 

thanks for all of the input,
as best I can remember, still looking for the sheet, 3 of the 4 cylinders were well under a 100psi with the lowest at 58psi.

I'll call the number today...

 

i have a 06 that has a vin# that could possibly have a bad head in the future is there any way that i can tell if mine has been changed numbers on head or anything?