[DanG]

Also wanted to add with regards to the "V6 is a bit over on power for the MTX75" comment.

Shock loading the trans and fighting the stick are the ways to kill this trans. The MTX-75 in my old (Now Topik's) turbo was a BONE STOCK 1999 MTX-75 with only a Torsen LSD unit installed. Stock shift tower, stock synchros, stock (and original!) blockers. 400fwhp and not a hiccup or a grind after 2 years attached to an F/I motor!

It comes down to this- Abuse and mistreat the trans and/or clutch, you're going to need a rebuild sooner rather than later (if at all). If you're shifting with more than 1 or 2 fingers, YOU'RE SHIFTING TOO HARD.

No double-clutching (up or down). Only very sparse "race-style" hard shifts where only your toe hits and lets off the clutch. Drive it right, it'll last. Drive it wrong, and it doesn't matter if you have an I4 or a 3L turbo- You'll break it!

With regards to the fluid- Synchromax or "honey" is best- However, that also being said (and I appreciate and respect Terry's weigh-in here), I ran Mobil 1 ATF in the above MTX- and after 115k miles when I pulled it for the turbo build, the insides were "immaculate", to use the words of the trans builder.