I just went to get some gas for my lawn mower and on the way back the truck would shudder and the rpms would increase while accellerating. I could get up to speed and cruising it did not shudder, just while accellerating. I checked the fluid when I got home and its a little over the hot mark. I have an aftermarket gauge installed and its reading around 130 degrees. This is on a 2001 4x4 xcab auto. Truck has 71k on it and had the dealer flush the tranny at 30k and 60k. Any ideas what the problem is?