Did some searching first, but didn't find anything.

I have a customer that has a 1996 Explorer and would like to know if/how to reprogram the PCM or other appropriate electronic module with his new tire size (or a code representing that size) so that his speedo reports the correct speed. Does anyone have any experience doing this? I know the MY2002-2003 PCMs have tire size in the VID, but I'm not as familiar as with the older vehicles. His dealer says his PCM will not accept the programming in the VID block, but will sell him another one that does (LOL). He also has info that says another module than the PCM could be the appropriate module.

Thanks in advance for any help or suggestions!

 

To correct the speedometer reading on 1996 Explorer one just needs to replace the speedo gearat the tailshaft of the transmission.
I went from 235/75/15 tires to 31" tires. I changed the small plastic gear ($7.23)from a 19 tooth to an 18 tooth gear. This put it right on.
Tire change 30.5"/28.89" = 1.0557 change.
Gear changewas19 /18 =1.0555 change.

CrazyBob