Hi folks,

I have acquired this NV3500 and would like to know about the speedometer drive...





There's no evidence of it anywhere, any clues?

 

What year vehicle is it from? Dodge eliminated the VSS in the trans in 98, I think.

 

It was from a 1998 RAM 1500 pickup...

I'm afraid I don't know what 'VSS' is. I would have assumed that there might be some kind of electronic speedometer driver if there was no cable of the old style.

 

VSS=Vehicle Speed Sensor.
If there isn't one installed in the tailpiece of the transmission, then the speedometer is getting its signal from the ABS sensor on top of the rear differential. If that's the case, it is good news for you because its already setup and you don't have to do anything with it.

 

Yeah, 98 won't have a provision for VSS.

 

Good news for me?

I would expect that any vehicle this will be used in will date from the '60s to '80s.

 

Everything I read shows the speedometer for a '98 Dodge truck gets it's signal from the rear ABS sensor also. Ray, you probably want the old school cable type speedo like mine has. My B150 van was probably one of the last models to use an actual cable from the transmission (mine is 5-spd manual NP2500/A535). Interesting that it does have a transducer mounted on the cable drive to generate an electrical VSS signal to send to the SMEC (TBI & pre-OBD-II). The mechanical cable part continues on to the speedometer.

As I recall most of your builds were carbureted, so you don't need a VSS for a computer to control injectors or for auto transmission shift algorithms. As a suggestion I have an ancient TomTom that's not even upgradeable anymore, but it still gets satellite GPS signals & displays my speed very accurately compared to the speedometer. Other than that I can't think of an easy way to get vehicle speed.

GL