Rebuilt transmission, now bent valve and pushrod

[John H Daniel]

I posted recently about what turned out to be torque converter stutter and metal in the trans oil. I took it in for new TC and trans rebuild. After a test drive they were driving it again to set shift points etc. and got a misfire and engine codes for cyl. 4. They tried to trouble shoot it thinking they had somehow caused it with the trans work. Took it to their engine guy… bent stuff in cyl 4.

It must be that during the test drive the AFM activated and subsequently had what I guess is the typical failure in cyl 4; resulting in bent valve and pushrod.

I bought it with 180,000 miles. I installed the RangeTech AFM disabler and drove it another 20,000 miles. I guess the few minutes they drove it was enough to have the AFM failure. Maybe I should have been unplugging the disabler periodically to allow the VLOM passages to clear out or something.

I need to consider the complete AFM removal.

 

[Dustin Jackson]

I posted recently about what turned out to be torque converter stutter and metal in the trans oil. I took it in for new TC and trans rebuild. After a test drive they were driving it again to set shift points etc. and got a misfire and engine codes for cyl. 4. They tried to trouble shoot it thinking they had somehow caused it with the trans work. Took it to their engine guy… bent stuff in cyl 4.

It must be that during the test drive the AFM activated and subsequently had what I guess is the typical failure in cyl 4; resulting in bent valve and pushrod.

I bought it with 180,000 miles. I installed the RangeTech AFM disabler and drove it another 20,000 miles. I guess the few minutes they drove it was enough to have the AFM failure. Maybe I should have been unplugging the disabler periodically to allow the VLOM passages to clear out or something.

I need to consider the complete AFM removal.

@John H Daniel So they had to remove the AFM disabler and drove it?

Sorry to hear this man, similar thing happened to me when it came time for me to smog my Tahoe I had to drive without mine.

I want to offer my words of encouragement that while things suck now this is a very fixable problem and you will have your Tahoe running again.

If you are planning on doing the repair yourself there are a lot of good people on this website that can answer any questions you have.

I am curious about the bent pushrod, in my limited experience I don’t see how a motor that is timed correctly could compress a pushrod enough to bend it.

 

[Geotrash]

I posted recently about what turned out to be torque converter stutter and metal in the trans oil. I took it in for new TC and trans rebuild. After a test drive they were driving it again to set shift points etc. and got a misfire and engine codes for cyl. 4. They tried to trouble shoot it thinking they had somehow caused it with the trans work. Took it to their engine guy… bent stuff in cyl 4.

It must be that during the test drive the AFM activated and subsequently had what I guess is the typical failure in cyl 4; resulting in bent valve and pushrod.

I bought it with 180,000 miles. I installed the RangeTech AFM disabler and drove it another 20,000 miles. I guess the few minutes they drove it was enough to have the AFM failure. Maybe I should have been unplugging the disabler periodically to allow the VLOM passages to clear out or something.

I need to consider the complete AFM removal.

Wow. A real life example of what many of us feared with only temporarily shutting off AFM. Bummer that happened, man. That head will have to come off to assess the damage, but I fear piston damage. It's possible to swap out a piston while the engine is in the truck, thankfully. And yes, happy to help you with working through the repair and AFM delete process if you decide to do it yourself.

 

[Geotrash]

I am curious about the bent pushrod, in my limited experience I don’t see how a motor that is timed correctly could compress a pushrod enough to bend it.

That's a fair point. Even if the lifter didn't compress when it was supposed to, piston to valve contact still shouldn't happen.

 

[John H Daniel]

They will start working on it Tuesday. If I'm very lucky it didn't score the cam, piston or other damage, but that's pretty iffy. Gonna be spendy either way...

 

[Doubeleive]

Keep the oil changes regular every 3k and this "might" not happen.

 

[Geotrash]

They will start working on it Tuesday. If I'm very lucky it didn't score the cam, piston or other damage, but that's pretty iffy. Gonna be spendy either way...

Yep. But still about $65K less than a new one.

 

[John H Daniel]

I paid $11k a couple years ago. Even if I have to spend up to $10k between the trans rebuild and engine fix/refresh, I'm not feeling too bad. I mean that hurts; not the kind of cash flow I was planning on. But a replacement would be in the $20k range and probably wouldn't have anything rebuilt.

 

[Geotrash]

I paid $11k a couple years ago. Even if I have to spend up to $10k between the trans rebuild and engine fix/refresh, I'm not feeling too bad. I mean that hurts; not the kind of cash flow I was planning on. But a replacement would be in the $20k range and probably wouldn't have anything rebuilt.

Great perspective. I wish more people on this earth had that kind of capacity for perspective.

It reminds me of the father of one of my high school best friends. He was a highly successful corporate lawyer, sat on multiple boards, could afford anything he wanted. I was at their dinner table when his wife was giving him grief over buying a new Honda Accord instead of a BMW or Mercedes. He looked me in the eye and said: "What Judy doesn't understand, Dave, is that it's all about getting from point A to point B. Every time."