I have a ProBuilt, name of company, 700R4 1993 in my C4. I only ran mid 11s with it. Fluid is still pink, and when I have taken pan off for inspections etc, not much for dust metal stuff in pan..
Rossler built for Lingenfelter, if I am not mistaken. That should say something for reliability..
If I have to do the transmission again, I would love to have Rossler rebuild mine..
But, ProBuilt has been awesome, knock on wood, since about 2010 maybe 5000 miles of hard street driving..

 

I just finished working out the bugs of my 4L80e swap. I messed with 700r4's and 4L60e's for years. I'll never touch one again for any kind of performance build. The 4L80e's cost so much less then having something else built. I got mine from a U Pull n Pay in Pittsburgh. I got a motor with the trans for $200 out the door. The trans had a tag on it from a shop showing that it had been rebuilt at some point. I put in a CK performance shift kit with accumulator deletes. Then I dual fed the main drum and installed Sonnex pump valves and springs. Topped it off with a 3600 rpm FTI converter. CK claims this combo will hold 700 ft pounds of torque. Even with the converter I don't have $1000 total into this trans.

You will need a 24" long piece of 4 1/2" box steel that is 1/4" thick wall and a good welder to make the C beam adapter. I had a steel 4130 driveshaft made with 1350 forged yokes from Action Machine. The gear ratios on the 4L80e are way better then the 4L60e/700r4. The only down side is the 4L80e takes more power to turn,. That just means you need to build more power I guess.

I'm running mine with a Holley Terminator X. But if you didn't want to spend that kind of money you can pull a 411 PCM and harness from a junkyard and have it programmed to be a stand alone controller for a 4L80e.

My only complaint is with the accumulators removed the shift from 1st to 2nd is real harsh. But other than that I've made some hard launches and burn outs and no problems yet. The best part is when I break it, I can just grab another one.

 

Yes they did and were recommended by John, when he was alive. He asked if the trans was stock when he tuned the car for the 383. I told him it was a fresh rebuild. He said "It won't last long" or words to that effect. He gave me a year and it made it 9 months and I didn't hit it that hard or often. He recommended a Rossler one that I beat on several times daily with no breaks.

 

Rosslers website said no longer taking orders on 4L60Es. Damn

 

Lack of demand and he does not need that work anymore, I assume. Guess you either DIY or have to hope that some other places that have to do it are decent.