Quote: 700R4, 4l60, 4l65E, or 4l70E's where meant to handle ~300 lb/ft of torque stock. They need some serious mods to handle a stroked BB in a heavy car. Heck, they tune the 4.8's and 5.3's down with the ECU just to get them to last in the trucks.
Horsepucky. I have countless friends running high 10's with LS powered F-bodies. Ported stock heads, big nasty cam, 4000+ converter, 125 hit of gas and bone stock transmissions with a good tune. My folks have had a tune in their 03 Suburban for the past 60,000 miles that cut torque management in 1/2, firmed shifts up and really dialed the a/f and timing in on the 5.3 in it and have had nary a peep out of the trans. Many of those miles are pulling a 23' Cobalt. 4L60's are a good transmission. Keep them cool and they'll last a good long time. My wife's TBSS (LS2) had over 60,000 miles on it post-tune and no issues with it either and it ran very very well for a 4500lb SUV with 400+hp.
