Its the VIN number that can cause trouble.

 

Not necessarily. The vin is only read thru the OBD port and the engine doesn't care what vin is in the PCM. If your state has the OBD inspections and you have replaced the PCM and not changed the vin # in the PCM, your truck will fail because the vin # doesn't match up to previous records.

I have a B&G flashed PCM that does not have my vin # and it runs perfectly with no codes. I just went thru state inspection yesterday so I had to change back to my stock PCM because of the vin#. It passed with flying colors so when I got back home I changed back to my B&G PCM.

 

I have seen instances where a vin mismatch annoys the ABS system..... I think......

 

My RT has 4 wheel abs and no problem whatsoever.

 

If you swap PCMs, you need MORE than just model year and engine.

ALL THIS needs to match:
1. Engine and year
2. Tranny
3. 4x4
4. Emissions (federal or california). Cannot swap a cali emissions PCM into a federal emissions truck (or vice versa)

Do they both match 2 or 4 wheel drive? That could be the problem.