I have an ‘02 2500 Cummins 4x4. I change every 10,000 miles I use Valvoline Premium Blue and Fleetguard Stratapore filters. Bought the truck a couple years ago at 130k, I’m at 250k now.

If I can just get the damned thing to STOP going in and out of lockup it’d be a good truck. I might switch to an NV5600 6 speed.
Other than that, no performance mods. No chip, no tuner no injectors, stock transmission. I’d really like to turn up the heat on it, what am I missing? More go power would be nice.