i just recently regeared my truck and my speedo is off 10 mph die to 4.88 gears and 40's can some one tell me if the speedo in a 97 dodge ram is gear driven or not. cuz im bout to order a sct tuner and hemifever says u cant adjust for tire sizes on those.. any help plz thank you

 

There is a gear driven signal generator in the trans, or transfer case. Have a look here, about 3/4 of the way down the page. There are various gears, and a calculator to help you choose the correct one.

 

Hi
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