It might help to raise the idle in reverse some. I have seen and heard this complaint when guys first install a high stall converter. Just a thought. Vince

 

Is this inherent to the 4l80e? Mine bangs into reverse from park, but it has no effect on RPMs, either with the stock converter or 3600 stall.

 

Mine does not make this noise all the time. It is a very loud bang. Everyone in the parking lot turned and looked

Here's a shot of the dust cover before I trimmed it.

 

Is that your flexplate grinding on there?

 

Pretty sure mind did the same thing.

 

One thing I have done in the past for the harsh engagements in reverse is to install an orifice plug in the feed hole for the low band. Then drill the hole to around a .90 and this seems to tame it down some. Normally the harsh reverse is when the trans is cold. You might want to look at the pressure tables for reverse to see if you can tweak them some to help reduce the feeling of the engagement if possible.

 

I believe it is the flexplate to converter bolts. I have a washer on the bolts in the actual install. I don't see why it would rub though as plate is not flat on the motor side like the TCI plate I had before. Should be lots of clearance and the bolts didn't hit that side with the TCI. Maybe the cover was bent.


I had already trimmed the other side when I had the TCI flexplate:

 

Well the trans definitely needs to come out now. I was still having issues with it wanting to stall idling in gear after a drive. Drove 60 miles today to watch some drag racing and it did it when we we stopped to buy our tickets. Idled nice for a minute, then all of sudden it was like there was a load placed on the engine that killed it. Re-started, idled nice for a bit, then same thing.

On the way home I pulled onto the highway and gave it about 60% throttle while already rolling which broke the tires loose, so I backed off and it just stayed in 2nd. 3rd was being commanded but it was not there. I picked up a little more speed and 4th clicked in, but didn't hold for long before dropping back to 2nd. Drove home in 2nd at 50 MPH and 3000 RPM.

Now that I think of it, it has been acting sort of like the TCC was sometimes locking/unlocking while in cruise under steady state conditions. Not sure if it was actually the TCC or the trans slipping/grabbing though.