rennat_2006

iTrader: (10)

So my recently purchased 2002 Tahoe for my 8 month pregnant wife needs a set of cylinder heads. I noticed that it had lost just a tad bit of coolant over the 2/3 weeks that we have owned it, I hooked my pressure tester up to it and couldnt visaully find any leaks. I did some digging around and found the Castech bullshit about coolant leaking through the drain holes in the heads due to the porosity so i tore the valve covers off. Passenger side valve cover was alright but had some sludge under it but the drivers side was full of what looked to be peanut butter.

Hooked my pressure tester up to it with the valve covers off and you can see coolant bubbling out around one of the center head bolts/oil drain passages.

So heres my dilemna, Obviously the tahoe needs a set of heads but i dont want casttech **** again. No way am i buying a set with the castech logo in them whether or not they are reman. So are their 862(casting number currently on it) and 706 NON castech heads out there or not? If so what year 5.3l do i need to be looking at for these?

Ive also got a set of 799 heads that i recently purchased from a member here for my lq4 going into my 71 nova. I paid $400 for them and put $280 into having them crack tested, valve job, milled 10thousandeths, etc. From what ive read these have bigger chambers than the 706/862 heads which would require about 15 thousandeths more milled off to be equal to the current head size. Only problem with this though is im assuming having them milled down the necessary amount is going to mean replacing the push rods correct? This i really dont want to do because of the extra down time.

JakeFusion

iTrader: (7)

It's a pretty big problem with Castech 706 and 862s. GM had a TSB on it that covered 5.3L from 01-06. So probably millions affected with the porosity issue.

I believe you can order a new set of heads for about $400 from your local GM dealer.

PNs: 12559862 or 12561706

rennat_2006

iTrader: (10)

Yeah its bullshit that GM hasnt had to do anything about it.

Ive been a diehard GM guy my whole life but after having to do head gaskets on my 06 duramax which GM is well aware and now this problem with cylinder heads that they are also well aware of im pretty pissed off. Duramax had 107k on it when they started to seap, Dealership i worked at for 18 months and was told if i ever wanted to come back my job was there told me i was **** outta luck and he wouldnt "goodwill" the repair. Now the tahoe has 125k on it and this, Im gonna give GM customer support a phone call tomorrow morning and see what they have to say about it.

I know those part numbers are on the heads themselves but neither partstaxi.com or gmpartsdirect.com find either of them listed.

01ssreda4

iTrader: (96)

I'd buy a $100 set of 241s and mill em 25 thousandths and roll out.

rennat_2006

iTrader: (10)

What is the difference between those and the 706/862? I would need different push rods going that route also which is what is holding me from using my 799 for my nova.

rennat_2006

iTrader: (10)

Looks like i found a set of non castech 862 at local wrecking yard that im picking up tomorrow for $125 each. After looking at multiple that had the castech logo(little battery looking deal) i couldnt find anything that resembled that on these so i should be good to go hopefully.

Fel pro head gasket kit and head bolts are on their way from summit and will be here next week so hopefully i can have these heads back from machine shop by friday and switch them out next weekend.

rennat_2006

iTrader: (10)

Also is it even possible and would it be worth it to have the valves taken out of my 317 heads and put into the 862's when they are at the machine shop?

Quick Ranger

iTrader: (2)

I've seen rebuilt 862 heads on eBay from Thompson motorsports for $300.

thompson

iTrader: (4)

We do have stock 706 and 862 castings as well as all other GM castings remanufactured. We also offer our TMS aftermarket castings CNC ported as well. Please give us a call if we can help you out.

rennat_2006

iTrader: (10)

So i found a set of 862 heads from the king yard saturday that didnt have the castech logo on them, dropped them off at the machine shop yesterday to be gone through. Machine shop got them pressure checked today and said they passed.

Heres my problem and hopefully someone(thompson?)with expirence can help, ive tried wiping down the heads on the tahoe and cant find a castech logo on them! Ive read that even cracked leaking castech heads will pass a pressure check at the machine shop is this correct?

Im scared now that i cant find the little castech battery logo on my heads that the ones i got from the wrecking yard that i also didnt see the logo on will do the same exact thing. Please dont tell me that the 706 heads are the only castech heads with the logo?!?!

thompson

iTrader: (4)

You can typically see the crack once they are properly cleaned but to ensure there is no problems I would strongly recommend using 862 in place of the 706. You can install them without having to do any tuning or major changes to the car and dont have to worry about the curse of the 706 heads.