Oxygen Sensor help........

[dojrs]

Are they Castech heads?

original GM heads. was castech one of GM's suppliers for their cylinder heads ?
i ordered these from allied motor parts in Austell GA. they have great turn around time and were extremely helpful and knowledgeable.

https://www.alliedmotorparts.com/?m...MI9LmT143b7wIVmuCzCh31XA8OEAAYASAAEgJxq_D_BwE

 

[Tonyrodz]

original GM heads. was castech one of GM's suppliers for their cylinder heads ?
i ordered these from allied motor parts in Austell GA. they have great turn around time and were extremely helpful and knowledgeable.

https://www.alliedmotorparts.com/?matchtype=e&network=g&device=c&keyword=allied motor parts&campaign=933839433&adgroup=48181143538&gclid=EAIaIQobChMI9LmT143b7wIVmuCzCh31XA8OEAAYASAAEgJxq_D_BwE

Yes, but Castech heads are highly prone to cracks. It's a known defect with them. Iirc they crack around the headbolts.

 

[dojrs]

Yes, but Castech heads are highly prone to cracks. It's a known defect with them. Iirc they crack around the headbolts.

do you remember the casting numbers that castech supplied? the ones that came off were 706 castings. the ones that I put on were 862 castings. all the research I read said the largest difference between those two castings was the casting material(s) used. one had minimally smoother interior surfaces, If I'm remembering correctly the 706 castings were the ones more prone to cracking. I had a set i traded for that wound up having a hair line crack between the 2nd & 3rd cylinders so i was not able to do the porting and polishing myself on those heads. that's when a friend advised me of Allied. I very well may have been able to keep looking locally and eventually found another set that were usable, but everywhere i called either did not have any or wanted more than a cleaned remanned set from Allied. So I just said the hell with it and went balls to the wall and got the CNC heads from them.

 

[Tonyrodz]

do you remember the casting numbers that castech supplied? the ones that came off were 706 castings. the ones that I put on were 862 castings. all the research I read said the largest difference between those two castings was the casting material(s) used. one had minimally smoother interior surfaces, If I'm remembering correctly the 706 castings were the ones more prone to cracking. I had a set i traded for that wound up having a hair line crack between the 2nd & 3rd cylinders so i was not able to do the porting and polishing myself on those heads. that's when a friend advised me of Allied. I very well may have been able to keep looking locally and eventually found another set that were usable, but everywhere i called either did not have any or wanted more than a cleaned remanned set from Allied. So I just said the hell with it and went balls to the wall and got the CNC heads from them.

Yes. Castech heads were the 706 and if I remember correctly also 862's. Not all 706 heads were Castech heads. The non Castech heads are fine.

 

[Rocket Man]

do you remember the casting numbers that castech supplied? the ones that came off were 706 castings. the ones that I put on were 862 castings. all the research I read said the largest difference between those two castings was the casting material(s) used. one had minimally smoother interior surfaces, If I'm remembering correctly the 706 castings were the ones more prone to cracking. I had a set i traded for that wound up having a hair line crack between the 2nd & 3rd cylinders so i was not able to do the porting and polishing myself on those heads. that's when a friend advised me of Allied. I very well may have been able to keep looking locally and eventually found another set that were usable, but everywhere i called either did not have any or wanted more than a cleaned remanned set from Allied. So I just said the hell with it and went balls to the wall and got the CNC heads from them.

Here’s the TSB.
http://ww2.justanswer.com/uploads/Bluegorilla/2008-12-05_142924_Coolant_loss_5.3.pdf

 

[dojrs]

Well the codes appeared again. They are....... 0053. I also have just experienced a weird limp mode type of thing going on. The T/C came on by itself. Dry asphalt road 80 ish degree evening. Random as hell, trans doesn’t act right like it’s fuel starved maybe ?.?.?... plugged in my cheap little code reader nothing. No nothing at all. Cleared the O2 code and the 0455 Bc I’ve got an evap leak somewhere also. Won’t take fuel so I’m thinking its between the charcoal canister and the fuel input possibly. Anyone else ever had this T/C happen to them? Any ideas ??