At about 70 mph on the Interstate I'm running about 3000-3100 rpms. I have 3.73s and tire size is 285/75/16. Is that to high or is that about normal and could it hurt anything?
Do you mean a 17" wheel? If so, it's only the tire diameter that affects engine rpms, not the wheel diameter.if you put a 17" tire you might get the rpms to drop a little.maybe the po had bigger tires if you wanna check you speedometer get a garmen gps unit.most tell your speed when your rolling.mine came stock with 16" and i found a set of stock 17" take-offs.now when my speedometer says 60mph my gps says 66mph..its worth a try
Sounds like it's time to invest in a new speedo gear. $40 and really only a 5 minute job even for a novice wrencher like me.I know my speedometer was off 7 mph when I had 31s. Now that I got 33s I'm sure it's gotten worse. So when I wanna go 70 I usually get my speedometer up a lil over 60