by TurboMax » Wed Jun 16, 2010 5:46 pm
I just swapped out the 3.909 ring gear & pinion with a 3.54 setup to improve my mileage. I'm currently running a 5-speed with stock 14" tires. Do I need to also swap out the speedo gear? If so, which speedo gear? I believe the stock 5-speed truck uses a 23 tooth speedo gear.