I have a 96 ram 4x4 5.9l auto tranny.........so as it goes my tans pan gasket was leaking and S seviced the trans, after that at quick test drive and went to work about 15 miles away no problems. Now here is where OH BOY comes in, I left work drove about a mile and the speedometer stops working and the tranny acts like it is slipping, so before you ask the tranny was rebuild about 40k ago and is now out of warranty, and when I did the tranny service there was no metal in the pan or visible sign of excessive wear. the only thing i did forget to do was replace the magnet back in the pan ( wouldnt think that would be a problem ) and was planning to re service in about 10k. so here is the question would the vehicle speed sensor cause the truck to act this way because it is not reading the proper speed ?

 

Yep. If the pcm doesn't know how fast your are going, it gets confused. Need to figger out why that isn't working..... need to find out if it's just the speedo that is flaking out, or if the VSS isn't sending a signal.

Check the easy stuff first though. Make sure the VSS is plugged in good.