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TSB Mysterious Coolant Leak

Does anyone know if the vertical marks betwen the springs (like in Pic #2) are normal?
 
I had the same problem with my 2004. Chevrolet customer service would not tell me if any assistance was available until a dealer diagnosed the problem. My mechanic had already done that. I had my mechanic replace the heads. I wrote Chevrolet and they offerred $1500. Then they said they would only give me $500 because the heads would have been " free" from a dealer. So I sued. My court date is next Friday April 27th. They have not responded to the lawsuit yet so I may get a default judgement.
 
merkava said:
I had the same problem with my 2004. Chevrolet customer service would not tell me if any assistance was available until a dealer diagnosed the problem. My mechanic had already done that. I had my mechanic replace the heads. I wrote Chevrolet and they offerred $1500. Then they said they would only give me $500 because the heads would have been " free" from a dealer. So I sued. My court date is next Friday April 27th. They have not responded to the lawsuit yet so I may get a default judgement.
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So how did that turn out?
 
I know this is an old thread but the casting number on the head to look for is 706. This can be found by looking at the head to the lower right of the valve cover (where the cover meets the head). I am having the same problem, 2002 with 170,XXX on the clock. Looking at a set of remanufactured heads (706 or 862 casting).
 
I was thinking I dodged that bullet but I only have 103K on her right now. I guess it could still happen down the road.  :eek:
 
Fowlhunter -

Where are you planning to get the reman heads from?  I can't decide if I am going to do the heads or drop in a junkyard motor.
 
Fowlhunter said:
I know this is an old thread but the casting number on the head to look for is 706. This can be found by looking at the head to the lower right of the valve cover (where the cover meets the head). I am having the same problem, 2002 with 170,XXX on the clock. Looking at a set of remanufactured heads (706 or 862 casting).
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It's an opportune time to drop a low mileage used 6.0 in it............
 
SgtSchultz said:
Fowlhunter -

Where are you planning to get the reman heads from?  I can't decide if I am going to do the heads or drop in a junkyard motor.
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I found a set of remanufactured 706 casting heads on Ebay, I sent a message to the seller to see if they are the Castech heads.
 
MyBigToy said:
It's an opportune time to drop a low mileage used 6.0 in it............
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I started down that road about three weeks ago and found a few nice LQ4 and LQ9 6.0 but thought I might just swap the heads and maybe cam and lifters for now?
 
SgtSchultz said:
If they are 706 heads, they are Castech. 
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I'm not so sure of that, the TSB directs the tech to look for a Castech casting logo instead of a casting number:

http://ww2.justanswer.com/uploads/Bluegorilla/2008-12-05_142924_Coolant_loss_5.3.pdf
 
Of this I am positive.  706 is the last 3 digits of the 8 digit GM part number.

GM does not order the same part number from two different suppliers, ever.

 
Doesn't make sense that the TSB would instruct the tech to pull the valve cover and the rocker arms to see if they were the problem heads when the 706 at least on the passenger side is in plain sight...
 
SgtSchultz said:
Of this I am positive.  706 is the last 3 digits of the 8 digit GM part number.

GM does not order the same part number from two different suppliers, ever.
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The 862 casting heads are the same as the 706, do you know where these came from?
 
Fowlhunter said:
I started down that road about three weeks ago and found a few nice LQ4 and LQ9 6.0 but thought I might just swap the heads and maybe cam and lifters for now?
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You know if you do that you will want a custom tune. I'd vote for LS7 lifters, and you will definitely want new trays also. You should be able to extend the shift point rpms considerably higher. I'm currently shifting at 6300 rpm on the stock lifters. I think someone we know with a yellow 03 Z66 is shifting around 6700 rpm with his new cam and lifters.
 
MyBigToy said:
You know if you do that you will want a custom tune. I'd vote for LS7 lifters, and you will definitely want new trays also. You should be able to extend the shift point rpms considerably higher. I'm currently shifting at 6300 rpm on the stock lifters. I think someone we know with a yellow 03 Z66 is shifting around 6700 rpm with his new cam and lifters.
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Once GM released the LS7 with its improved lifters they started putting them in all of the non-DOD engines and discountinued selling the older ones.  If you go to a GM parts counter and ask for lifters for your older 5.3 they will sell you the LS7 lifters as stock.

And yes, you can rev them higher before getting lifter tick!   :cool:

Also agree with MBT about the lifter trays. You'll need 8 of them and I think you can find them online for about $4 each.  With an aftermarket cam you can find a lot more power up top.  You'll also probably need to do a valve spring upgrade unless you get a pretty mild cam.
 
MyBigToy said:
You know if you do that you will want a custom tune. I'd vote for LS7 lifters, and you will definitely want new trays also. You should be able to extend the shift point rpms considerably higher. I'm currently shifting at 6300 rpm on the stock lifters. I think someone we know with a yellow 03 Z66 is shifting around 6700 rpm with his new cam and lifters.
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I'm back and forth between heads, cam, springs & lifters or a crate engine. I know the price of the crate engines but at least I would have a warranty, if I were to go the junkyard way with an engine then rebuild it I wouldn't have a warranty. I'm still torn but I need to get my act together sooner than later.
 
TSB is just a bulletin telling you what the problem was and how to fix it. The people that got theirs done for free were still under warranty.

I need to see if my truck has these heads as an '03. I had lost 3/4 of a gallon of coolant over a year period but was told the water pump was leaking so I replaced that first.

At 260K+ miles I guess if this is an issue with my truck I will keep it in mind and look at getting a 6.0 and upgrading some components on it.

Rodney
 
I have the dreaded 706 casting... And have been trying to track down a coolant loosing issue that I have been having for last year...

So I guess I will be having a 6.0 in my future...

Rodney
 
Is your oil milky looking? I thought I had it and it was a bad seal on the water pump. Just enough to loose a bit of water each day, but not drastic.
 
So far I topped off the coolant at about 200 miles and after more than 1000 miles I haven't lost any more coolant so I MIGHT be good for now. But certainly will be considering getting a 6.0l in the future. Probably will be over 300,000 miles by the time I get the 6.0l. We will see what condition the truck is by then. (When I retire in less than 5 years I will have more financial flexibility and will be looking to upgrade this truck dramatically for off road usage.)

Rodney
 
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