What 628 is saying is that for the RPM, the gear the Computer has selected along with or not it applied the TC Clutch does not agree with the information it is getting from the PSOM.
So the computer thinks it has detected that the Transmission has slippage.

I would get that speedometer working right before doing anything to the transmission.

 

What would be the first step in fixing the speedo....what do i have to change and where is it....lol...im new to all the electronic crap in vehicles

 

As said above you will need to either replace the PSOM or fix the rear end.
If the signal is week from the rear end you might try unplugging the RABS module and see if it works OK then. If so the gap may not be right between the VSS and the tone ring or a bad RABS module.

 

ok...thanx...sorry for sounding stupid

 

unplugged the VSS and the damn thing shifts fine (go figure) I'm gonna pull out the "NEW" VSS and see what I can find...what in the rear should I check....do I have to do anything with the gear set (please say no..lol)

 

ok...getting ready to pull the rear diff out....what am I looking for that might be screwing with the VSS....and what is the best gear oil to put in...I was gonna go with Lucas because so far I love all the stuff the make....thanx

 

youll be looking at the Tone Ring, make sure its not bent or missing teeth.

If the rear diff has a LS in there be sure to add your friction modifier otherwise the LS will get damaged.

just curious what size tires are on the truck? its possible the PSOM needs recalibrated to the current tire size. it this isnt set correctly to what your running it will cause the tranny to not shift properly or accuratly.

you replaced the TPS, but did you make sure its operating in its proper range?

 

don't know if you read earlier post kemi...when I unplug the vss...the truck shifts good...it has a new vss in it but I don't know how to check if it is good. The truck has stock everything....tires and all (so far...lol) will I be able to tell what the tone ring is just by looking at it? ...I cant find crap as far as pics of my diff...thanx

 

The tonering:


/

 

Damn...thanx bud...talk about being thurough...lol

 

ok...tone ring looks fine...I guess the next thing to check is the PSOM itsself....is there a way to test it or just buy another one and see if it works

 

does my truck have a 4wabs?....is there any chance that it could be an issue?

 

You have RABS for the rear only (2 wheels) and yes its moudle could be bad. Just unplug it and see what happens.

 

thanx sub....I thought I only had one but had to ask...when I unplug it it shifts fine.....but it's a new sensor...is there a way to check if the new sensor is bad?

 

Are you saying when you unplug the RABS module it shifts fine?

Did you check the air gap between the tone ring and the VSS?