Im trying to diagnose the transmission problem on my truck. When I am driving up steep hills the tranmission hesitates to gear down, it is an automatic and jumps to third and sometimes quickly down to second. When it jumps down a gear and I try to maintain the same speed there seems to be a loud rattling from under the vehicle, im assuming its coming from the transmission. The higher the RPM's the louder the rattling so I let off the gas and slowly climb the hill. This only happens on steeper hills when the transmission has to downshift, also struggles more with weight in the back, i.e. snowmobile. I have been researching and this might possibly be a torque converter issue?

 

my ford used to do the same thing when it got hilly. I think it is a confused comp...you should just put it in a lower gear until the road levels out a bit.

 

Checking the fluid levels wouldn't hurt either. Gravity works so the fluid is prolly running to the back of the trans.