I have a 97 dodge ram with 318 cid and auto transmission. It does fine until you get to 45 mph when it should go into overdrive then i starts to jumping like big knotys on all tires. You can turn overdrive off and it will not Jump and bounce. When I check for code I get miss firing for several cylinders. Any help woul be appreciated.

 

You might have better luck posting in the 2nd Gen section.

https://dodgeforum.com/forum/2nd-gen-ram-64/