I have a 1997 Dodge Ram 1500, 5.9L 16V V8., after when I get to the speed of 45 and 50 mph, my truck starts to buck and jerk. What is the problem? I also hear a squeaking noise, sound like it's coming from the belt,. What could this be?

 

Try the 2nd gen forum.

Then check your cats.

 

the lock-up on the converter isgoin in and out of lockin overdrive! have a durango that did the same thing, took it to the dealer tookem twice to finally fix it (was warranty work)