I have a 2002 f-350, and I was pulling my 5th wheel home the other day and the automatic transmission temp gauge started to climb into the yellow caution area. I was coming up a steep grade out of a canyon, but I had the truck out of overdrive to help the transmission out, but it still started to over heat. Any idea as to why, and how do I fix it.

 

don't understand that one,our 2002's have the larger tran's cooler right from the factory unlike the early 1999-2000's, I pull a 32 ft 3 slide sunnybrook,truck and camper, at the scale I weigh 20900 # and i've never been over 190 degree's on my piller mount tran's temp,the factory gauge is little more than an idiot gauge,have some one put the piller mount tran's,ext,and boost gauge's on ,how many mile's do you have on the tran's oil??,have you ever changed it, better pull the stick and see if it's look's burnt or if it smell's burnt,I change mine every 25000 mile's weather it need's it or not,if you think it got hot you best change it anyway,need more info on your truck,how many total mile's,have you changed the fluid ever.

 

Prints,
It could be a bad sender for trans gauge. Mine started reading 200+. Take out the sender and ground the threads of the sensor to the the tranny using alligator clips. Take the sensor with a thermometer and put it in boiling water. With the key on (yes have someone help you) check the gauge and the thermometer. Mine was 50 degrees off. Called Banks and got a new sender for $18.00. Problem solved. Good luck. Tom