I ran two years on a FLT level 6 4L60E with 500hp at the wheels. Never had any problems until the oil pump decided to fail which I believe is unrelated to the power. I ended up switching to a built 4L80E since I planned adding boost.

 

The 4L60E that I built for my Camaro is still alive and has survived 4+ years and at least a couple hundred track passes at 600+ rwhp @ 3600# raceweight. Stock input/output shafts and stock 4 pinion planetaries. There's some tricks to making a 4L60E survive. The clutches and steels have to be setup right, tighter tolerances than what ATSG recommends. Hardened pump slide spring, unbreakable vane rings, etc, etc....

 

i been wondering for 4+ years or so when my 60E will let go now it sees over 700+ quite a few times a weekend at the track

but i will say this if and when she does let go i wont go with another

 

Its been a long time scince ive been on here, but I figured id say I went with a..............nother 60e, and it was purely a financial issue and a lack of space/time to work on it, I went took the risk and bought it from a guy i have never met, and so far I couldnt be happier but then again its only been about 3 or 4 months, everything works great 2nd gear is a snap and the rest are very firm, I got an actual reciept from the guy with his name address and all the parts that were used, I also went with a Circle D 3200 stall and I am really lovin that! Had the install done in a day and drove it easy for a couple weeks before i abused it to much, we will see how long this thing last.

 

Be careful on the snappy 1-2 shift.
Good for breaking output shafts.. ive done it a few times.