Jack,
I'm with you when it comes to driving up and down hills. Like to save the brakes as much as possible and keep the engine cool, so when the tranny starts shifting up and down, into 2nd it goes! One of the extras that came with our Suburban is a transmission temperature readout. So now I'm able to track that too. On these long western mountain passes. I was surprised at how hot our transmission would get if I'd push 2nd gear when climbing a grade. I'm not sure what the "redline," tranny temperature is
, but I strive to keep it at or below 200F. Last spring, before our long summer towing trips, I had a secondary transmission cooler installed. Really paid off going through the Big Horn Mountains in Wyoming... over 20 miles of a constantly climbing 10% grade with a bazillion switchbacks! I just left it in 2nd, maintained a 35 mph speed, and enjoyed the view! Engine and transmission both stayed nice and cool.
Jim
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