Tire size change

I changed to a different tire size, which is exactly 2.5% larger in circumference, according to flatland GPS measurements/mile markers vs. original VMSpc. OEM tires were 235/80/22.5" while the replacements are 275/70/22.5".

I'd like to reset just one 'trip odometer', the one I have set to track engine parameters from day one, to *not* reflect this 2.5% increase except from a certain mileage point, about 62K miles. I have made adjustments for the current odometers I use, of which there are four, I'm an info-geek, but that one I'd like to yank 2.5% out of the first 62K miles of data so I have a dead-on mileage reading for the 'lifetime' odo.



Kelly Bradley
currently on the road, in Pigon Forge, TN at the moment

I have just the thing.

Click on the "Odometer Mucker-Upper" thread (link). You can tweak the starting values of the odometer to compensate for the tire size. (You could also tweak the offset values for the engine corrections, but that would affect all your odometers.)

Odometer tweaker

Thanks, Martin!! This is going to work out perfectly, I'm pretty sure.

Kelly B
'99 Bounder Diesel 39Z, Cummins ISB 275 w/VMSpc showing a corrected 10.0 MPG over its 100K miles