mitchntx

I didn't know. Good info. So the 247K miles, many towed behind an RV seems awfully suspect as was said earlier. Does the odo only get a signal from a reluctor in the trans or would it also pick it up from an ABS wheel sensor?

2001 electronic cases don't have a neutral, right?

I'm looking at a 2001 GMC that has 247K miles on it and the owner claims that the majority are tow miles behind his RV. The odometer is data stored in the ECM. The miles still rack up using constant power to the ECM? Also, I've always been taught that towing without disconnecting the driveshaft was hard on the transmission. I assume that still holds true? On a 4WD with auto hubs, the drive line has to be disconnected as well? Or just selecting 2WD unlocks the front hubs and no engagement of teh front DL and transfer case?