Have 60,000 on my truck and did a full trans filter and fluid change.

I put on a new Revmax deep pan and revmax thermal bypass too.

All said and done i refilled with ATF+4 fluid it took 12 1/2 qts of fluid.

I ran it around a bit to make sure all is well.

Everything around here is 7% grades, temp, outside is a brisk 20* and after driving around my trans temp reached 138* drive time about 30 min.

I let the truck idle for about 15 min before I drove it to de-ice windows and warm up.

I do have a bra on the truck with all but 1 vent closed.

For those of you worried about the thermal bypass not allowing your trans getting up to temp in cold weather.

I don't feel you will have any problems.