rawlinss 14 Report post Posted February 10, 2013 Took Tom Tom GPS with me today to check out the speedometer. It is off by about 15 miles an hour. When GPS says I am going 55 the speedometer reads 70. Any suggestions? Thanks, Sandie Quote Share this post Link to post Share on other sites
maxum96 32 Report post Posted February 10, 2013 Took Tom Tom GPS with me today to check out the speedometer. It is off by about 15 miles an hour. When GPS says I am going 55 the speedometer reads 70. Any suggestions? Thanks, Sandie Change the gear on your speedometer cable. Quote Share this post Link to post Share on other sites
rawlinss 14 Report post Posted February 10, 2013 called CJ Pony, told em what size tires and rear end I have and they set me up. Before- 3-17 gear After-3-23 gear Thanks Maxum!! Quote Share this post Link to post Share on other sites
maxum96 32 Report post Posted February 10, 2013 Anytime. That's what I did when I built my car. I talked to Don Walsh from D&D Performance (a super nice guy and a former Ford transmission engineer and SVO drag racer) and he helped me out with that same issue a few years ago. Quote Share this post Link to post Share on other sites
