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I Think I Have Cracked Castec Heads!

Mizz

By Mizz
in Ask A GM Technician

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Mizz Enthusiast

Mizz

Posted
Posted

Hello all, This weekend I traded in my 08 standard cab 5.3l silverado (23k miles) for a 02 4.8l extended cab silverado with 106k miles. Money is getting tight and I really needed a cheaper payment and a truck with room for all the kids.

 

I was randomly reading through the forums when I came across a thread about loosing coolant very slowly. Turns out it was because of cracked castec heads. This got me thinking, since I got the new to me 02 silverado I have put 1/2 a quart of oil in it and maybe 1/8th gallon of coolant in it. Honestly I didn't check the oil or coolant level at the dealer but I did do a quick check to make sure they were both the right color and they are, the oil looks fine and the coolant is redish but when I added the oil the other day I noticed under the oil filler spout the oil cap had what looked like rust under it and the tube had white jellyish or oil/water mix coating on it. At first I didn't think anything of it and wrote it off to condensation but after reading the cracked castec head thread I am worried now! There is absolutely no engine noise what so ever like the other people had lifters tapping and I have not had the truck long enough to know if it is loosing oil and coolant. There is no coolant smell or any other smells at all coming from the motor but the exhaust does seem to have a lot of condensation coming out of it before the engine warms up. How much will it normally cost to replace a set of heads on these trucks?

 

Here is the kicker! I have not finished the paperwork with the dealer I got the truck from. He printed me a bill of sale and that was all (we are waiting on papers from the bank). Should I go ahead and try to keep this truck? Is there a easier way to tell if the heads are cracked besides taking the valve cover off? I don't have time to do that, or money to change the heads or worse the entire motor.

jtstacy77 Enthusiast

jtstacy77

Posted
Posted

I have very similiar problems with an 04 silverado. I just added a new post about extreme coolant loss. My loss started slow but has gotten progressively worse. If you can take it back, you probably should or at least get an extended drivetrain warranty!

tylerjenkins92@aol.com Senior Enthusiast

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Posted
Posted

My oil cap gets this brown crusty stuff on the bottom of it, but the tube has nothing in it but oil, and it doesn't have castech heads. The best way to tell is to just fill the coolant up and drive it.

txab Senior Enthusiast

txab

Posted
Posted

I would have it diagnosed before you finish the paperwork. Pulling the cover is the best way to see if you have the castech head issue. Or you could have a head gasket leaking. Will the dealer give a 30 day warranty?

rdnkcpa Enthusiast

rdnkcpa

Posted
Posted

Get a warranty from the dealer. The only way to check is to pull the valve covers. This is not an inexpensive repair. I'm right around $1,600 doing all the work myself.

tylerjenkins92@aol.com Senior Enthusiast

[email protected]

Posted
Posted

1600? I don't know how. I just bought a set of used non castech 862 heads, which are what the 5.3s have(same as the 706 also) for only 125 dollars shipped of ebay, so it's not so exoensive, especially when you do it yourself.

rdnkcpa Enthusiast

rdnkcpa

Posted
Posted
1600? I don't know how. I just bought a set of used non castech 862 heads, which are what the 5.3s have(same as the 706 also) for only 125 dollars shipped of ebay, so it's not so exoensive, especially when you do it yourself.

 

I did not buy used. I purchased new bare heads, had a machine shop grind the valves, test and replace the springs where necessary, put new guides and seals in the heads. Heads were $780.00 which included pressure testing of the old heads + seal kit which includes new head gaskets + new head bolts + all new lifters + new spark plugs & wires + new water pump. Quickly approaching $1,600.00.

 

I did not want to buy used, especially off of flea bay. If you go used you can do it on the cheap.

Mizz Enthusiast

Mizz

Posted
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Posted

Well I changed the oil tonight, it looked okay, there was no sludge. It may have had a faint redish tint to it but its hard to tell. I only had a shop light under it. The truck was about 1500 miles over the recommended change mileage. I am hearing a very light tapping noise at idle now, it goes away with rpm and seems louder from underneath the truck.

 

I'm probly going to pull the valve covers tomorrow and see what they look like. Are the valve cover gaskets reusable or will I for sure need to get new ones?

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