92nsx

180. Very nice! I like that, a solid real world answer.

I wonder since Im AWD that also would make the tranny run warmer then everyone else that are pulling in 2wd? Twice as many tires putting the powa down to the ground.

Ya so far I have no complaints with Dexron VI or the ranny. The last time i changed the filter i added a drain plug to the pan. I pull the plug when i change oil to keep fresh stuff in there. It only changes 2.75 QT's a time.

I.D.C.E.

Your numbers are off. My rig (2010 Sierra Denali 6.2 6L80 AWD) is 16,380lbs, on the tow from NJ to Florida i never saw over 180. The only time i did see it get up to 180 was when i tried cruise for a little bit. Off of cruise it would keep around 150°.

The same powerplant so we should be relatively close.

92nsx

Ummm...... Now that is making me wonder... yours must 3/4 ton? Maybe larger tranny cooler? Other wise its the same pull rig.

I did noticed when the tranny temp would climb to 220 the engine temp gauge would also creep up a bit from normal.

This spring Im thinking of flushing the radiator out. See if there is some crap in it or something.

I.D.C.E.

I am the one in the front. In 2010 they did not introduce the HD Denalis yet so I am a 1500. We have the same truck just different looks. That's why I offered my information. In this cold weather we are experiencing in Jersey, on the highway I was monitoring the trans temp since this thread and it has been around 102-104 climbs to 110 around town. I have done transmission services every 25k truck has 62k on it now. I use oem dex 6 and an oem filter. I have a trans shop so doing extra maintenance is nothing to me. My Pop's 04 Yukon Denali just cracked 400k a few weeks ago. Must be doing something right lol. Did you inspect the cooler and your fans? Make sure you didn't suck up something interfering with air flow. If you have a scanner or friend that does make sure they all work by going through the functional tests. My fan barely ever comes on unless it is the summer in traffic with ac on. Hard to diagnose over OSO but you have to figure it out somehow.

wannabe

Radiator flush will help. have the trans fluid swapped to if not done in a while. USE OEM Dex 6 from the list of suppliers I posted earlier.