Quote Originally Posted by wickedfrisone View Post
I forgot to add, so aren't these really high temps (at least 210+ ish) not still bad for a transmission's lifespan? Or does everyone who wants theirs to last over 150k have to eventually shell out the extra money on a separate cooling system?
Some say yes, some say no. GM and some tranny experts seem fine with these temps. IMO, going over 200 is to hot. I change my fluid twice a year to make sure it is fresh and as non-burnt as possible. I hate when my tranny is hotter than the engine. Funny thing is when sitting at a light, the temps climb. Get going, engine temps drop right away, trans temps take forever to drop. I've always said that the factory cooler is crap and causes the hi trans temps.



Aaalso... would a cooling system flush and maybe even trans cooling line flush/cleaning not help at all either?
No, unless you have blockage somewhere.