I posted this in another thread with no response so I'll try again;

I finally bought an X3 to correct my speedo. I have 33's with a 4.30 gear(I think stock was 225/70/15 with a 3.55). I thought my truck was over geared, or....putting on miles too fast. I used 615 for revs/mile and it seems like it's even more in that direction. Does a lower number revs/mile = higher speedo reading and odometer runner faster?

 

lower revs/mile = lower speedo reading...

 

You did receive a response in the other thread. Check it out.