Speedometer/ Odometer changes
#12
Are you certain of this? It's more conventional to either mount the speed sensor at the transmission output shaft, the transfer case, or a wheel (front preferred, since that is less likely to introduce speedometer error caused by tire slippage). I've never heard (not that I'm fount of all things mechanical. LOL) of using engine RPMs to calculate speed--seems rather prone to errors. And, as far as gear ratio: There are plenty of folks on this board who swear that after regearing, their speedometer did not need recalibration. I've never seen that resolved, since there are also folks who argue the opposite (and I do know that my Hypertech has a place to program gear ratio).
#13
Well I do not know how it works, but I know for a fact that my Rubicon on 30" winter tires gave wrong speed as measured with my GPS, and on the summer 35" also wrong speed, but the other way around. It used to shift really rough on the 30", but not so bad on 35". When I got my Procal, the speed re-became accurate for both, and tranny shifts much smoother !!
Dealer says I was running for big problems with the tranny if I did not reprogram, the specs from Jeep is 3% error, over that, you will dammage. Now the dealer could adjust only from 28" to 32", you NEED the Procal (or other briands).
Dealer says I was running for big problems with the tranny if I did not reprogram, the specs from Jeep is 3% error, over that, you will dammage. Now the dealer could adjust only from 28" to 32", you NEED the Procal (or other briands).
#14