95 rodeo speedo question

on my 95.5 rodeo 5spd the speedo is off by about 5 mph. to my knowledge the vss has never been changed. I know tire size will throw it off, but the truck sits on 245/75r16 tires. any ideas? does the vss possibly need cleaning, or is there a way to adjust it? The only time I know of the instrument cluster being fully removed was during a heater core change. Could that have something to do with it??

Your speedo IS going to be off, you're running slightly larger sized tires then oem stock size. Personally, I would just keep that in mind and leave everything well enough alone.

I'm saying this because I'm running tires 2 sizes taller then oem size, my speedo is off by 7-8mph I think, not 100%; I've ran it this way for over 2.5yrs without concern.

I personally will not be correcting my speedo, I just remember to keep that in mind when cruising at a certain speed.

Funny thing is, I can pass one of those set-ups that tell you exactly the speed you're going, mine is generally only 2-3mph off what their radar will say.

I've learned more then once when you start messing with parts that really don't need to be messed with on older vehicles, other parts that either had to be moved or shifted to get to the repairable part start failing as well and it becomes a viscous cycle.

Just leave her alone and drive!!!! Nice to hear of one with over 200k btw.

Thanks for the input. I won't worry about it anymore.
208k miles and still running strong!!!
I love my rig!