SandSOrrell wrote:
I've just returned from a trip from Texas north through OK, KS, NE, SD WY, ID, UT, CO, NM, and back. Lots of long mountain grades. I have a 2013 Chevy 1 ton Duaramax/Allison DRW 4X4. Trans temp never got above 180 as far as I know (and I checked it often in the mountains). 240 would be alarming to me. But again, I've got a new truck with less than 12,000 on it.
I don't want to start a brand war here but my Chevy D/A is a towing machine! On I-70 through CO, I set the cruise at 60, put the trans in Drive, Tow/Haul mode, and exhaust brake on and the truck never broke a sweat and I VERY seldom had to even touch the brakes on the downhill grades. I'm very happy.
Again, a lot depends on where the readings are taken. The 68RFE in my 2011 RAM runs around the same temperatures as your D/A, don't think I have ever seen 180 pulling.
This is where the new transmissions are quite different. Their torque converters remain locked in most of the lower gears where the old 4 speed just locked in 3rd and OD unless modified. If the converter remains locked, high ambient temperatures don't effect transmission temperature very much. Try keeping your eye on the tranny temp when you are spending a lot of time trying to back your rig into a difficult spot. You will see it go up then.
