Speedometer squeezes **** between the sheets...

Hello, new member looking for suggestions. Hoping this is the correct forum location.

Just picked up a 1995 2500 SLT Laramie 4x4 where the only disclosed "issue" was a non-working speedometer. PO stated that it stopped working about 4 months ago.

Sure enough, it wasn't working.

After an initial search for a solution, I figured I needed to replace the VSS on the transfer case. Doesn't seem to have solved the problem. After replacing the sensor and soldering in the associated pigtail (as per this video: https://youtu.be/jBQcG_GeaA4) speedo was still dead for about a block, then the needle swung up to speed until I hit the brakes and decelerated where it then dropped back down to zero (like a rock, not as the truck slowed.) Then, about 120 freeway miles later, the speedo needle swung back up to the current 75mph speed and held in the 70-75 range until I reached my exit 50 miles later. Decelerating onto the offramp the speedo dropped back down to zero as soon as the truck started to slow and stayed at zero until I parked.

To note, there are no ABS or Brake lights active on the dash, and the cruise control is also non-functional. I don't think the "dash function test" works on the '95 as it has analog odometer/tripmeter and OBD1. So I don't know how to check the speedo gauge for functionality.

What does the hive mind have to say? Any suggestions for next step(s)?

Thanks in advance.

Probably going to pull the instrument cluster today or tomorrow. Anything specific to look/test for in there? Which relays to check? Are there any "culprit" connections to examine? Is the speedo module worth replacing?

Can't remember the procedure for it but there's a cluster self test/calibrate. Quick google search should pull it up pretty easily.

Edit: disregard, 98+ only.

If I swap in another gauge cluster from a salvage yard, as long as it's a cluster with tachometer, are all clusters interchangeable 94-97 / 1500, 2500, and 3500?

Excepting Cummins dashes labeled "Diesel Fuel Only"...

94-95 had obd1 computers with lots of old analog add ons. 96-97 is obd2 with everything run through the pcm/ecm.


"Talk is cheap. Whiskey costs money."

Yeah, there is that...

So let me rephrase, are the 94-95 clusters interchangeable between the 1500/2500/3500 as long as they are gas and include tach?

Or do I have to source from a similarly spec'd unit ('95 2500, 5.9L gas, SLT Laramie, reg cab, long bed)

Thanks again.

T-Bone McBeef said:

Yeah, there is that...

So let me rephrase, are the 94-95 clusters interchangeable between the 1500/2500/3500 as long as they are gas and include tach?

Or do I have to source from a similarly spec'd unit ('95 2500, 5.9L gas, SLT Laramie, reg cab, long bed)

Thanks again.

Click to expand...

Clusters from 94-95 are interchangeable on all v6 and v8 engines. The diesel cluster has the wrong tach.

Any other obvious things to check that could cause the VERY intermittent speedometer function after replacing the VSS?