First off, have a 2001 auto. , dana 70 suregrip, 3. 54 gears. About 5,000 miles ago I installed Amsoil series 2000 75W-90 gear lube, I also installed a MagnaGuard aluminum differential cover. This is the type that has the plastic sight glass with 2 magnets and when the oil drains down the magnets it catches the metal particles. But anyway, here is my question, After I drive the truck for about an hour or so at highway speeds I crawl under there with a creeper and you can literally not hold your hand on the cover for even 1 second. Now to me, that would be in the 160 to 180 degree range, after I'm done driving the truck, when I lift the hood and touch the motor parts and I know the motor runs at 180 degrees, it feels the same as the rear differential cover. Do you think this is too hot or is this normal? Don't seem normal to me. The cover even gave me 2 to 3 extra quarts of capacity. What do I have to loose to try LE oil? If it doesn't change the temperature then I will just leave it in. Can it be any worse or better than Amsoil? I guess I need to get one of those $100 napa point and shoot thermometers and then I will know the exact temperature. Any advice? Thank you in advance for any info on this matter.