I'm considering buying an xterra, and if I do most likely I'll perform the calmini live axle swap on it. What are your opinions for an automatic transmission and the swap? Would the larger tires and possible drivtrain stress be a bit much on the automatic?

That's why you regear. If you have 4.90's to begin with, those should be fine with tires up to 33". 5.14's come recommended for anything bigger.

I'm running 4.9 in rear and 4.88 in front with an auto with Calmini TC gears and it works great. On the highway it works fine at 75/80 mph.

-Doug

Gearing, gearing, gearing.... thats all I have to say.

I'm SAS'd & running 5.14s front and rear with just 33s.. and my auto tranny is pretty happy.

I'm ordering the Calmini crawler gears today though. On the really rough stuff where the tires need to claw up vertical obstacles, the tranny still complains a little. The more gearing you can get, the happier the tranny will be in the long run.

Less torque converter slip = less heat generated = a longer lasting tranny.