I just recently purchased a 2008 Suburban for my wife and noticed the transmission temperature seems to stay in the 160-175 degree range. While this doesn't seem too hot, my 2009 Silverado ext cab with the same engine (5.3), rear gear (3.73), and tire size (20") runs consistently around 150-160.

Does anyone know what the normal range for transmission operating temps should be for a 2008 Suburban?

 

I know this is an old post, but I want to know and can't find the info.
Did you ever find out an normal Trans Temp Range? With and without towing??

I have a 2007 5.3 K1500 LTZ with 4.10 ratio and OEM HD aux trans. cooling system., I towed an about 6K boat across the front range between Glendo, WY and Denver, CO. I hit 212 deg. once and that was my highest temp. going up I-70 for only a few miles, before heading south on falter ground.. Ran mostly at 196-205 deg. Lowest at 175 in a rain storm. Temp out about 85 deg. It has gauge, but no range, seems strange. We slowed down to 60 going up bigger hills to keep the trans. from shifting too much.Other wise ran 75-80 (the speed limit).

Worried when I take it to the mountains my temp will go much higher and the Suburan doen't say how hot hot is for this Burban??.