Quick question. ok 96 4x4 ram 5.9 magnum auto. Running great. one day i'm driving down the highway and about when the overdrive kicks in, and driving at around 65 MPH truck starts to sputter and back fire a little in the engine bay (loud pop). You can also feel it inside the cab truckvery sputtery jerky foward movement.

No problems at idle runs great no noises. oil pressure ok temp normal oils good etc. I know my cat is giving my o2 sensor a workout (ses light on) but its running perfect otherwise just a little rich to make up for the o2 sensor reading. its been running with this cat/o2 problem for about a year now. problem just started yesterday

any thoughts? I'm thinking fuel filter or moisture some bad gas?

 

I think the cat is finally giving up. You can take it to a muffler shop and they can do a pressure test.