I posted this in the 2nd gen Ram section and was askwed to post it here. Sorry if you already readi it.

I have a 1999 Dodge 2500 diesel. The transmission was shifting erratically at 40-45 mph. I replace the throttle position sensor, had the chip re-programmed per a TSB all did nothing. I even replaced the lift pump and had the trans serviced. Nothing. The other day the injector pump failed. The Computer actaully failed on the pump with a P1688 code. Nothing mechanical. I replaced the pump and the transmission problem went away. It now shifts very well at all speeds. If you have the same truck and are experiencing erratic shifting and have not replaced the original pump, get a pump.

 

what pump would we be talking about?

 

'99 would have the vp44, right?

If I was the OP though, I'd replace the OEM lift pump with an Air Dog or FASS because the OEM lift pumps are known for being the weak point.

 

i have a 96 12valve. so does it affect me?

 

Yes a VP44 and yes I replaced the OEM lift pump with one I bought at autozone.

 

If you have a vp44 injector pump it could.

 

You have a P7100, which is a better pump than the VP44. You do, however, still want to make sure it's getting proper fuel pressure and flow.

No matter what truck, I'd recommend a FASS or Air Dog - they filter out a lot more junk and flow much more.