Does anyone know how to find out what size gear I will need for my trans to correct my speedometer (I have the 1997 which still used the gear in the transmission for the speedo). I will have 4.10 gears and 275/65-17 tires?
See signature below if that helps.

 

Anyone???

 

According to the chart at http://www.finer.com/Internet/pages/speedo.htm
you need a 21 tooth gear. It is part number DOOZ17271B. I just bought one and it is the purple gear. Total cost was 6.86.

 

Thanks GeneKend, my local Ford is not the most user friendly. I like to know what I am looking for when I go...

How do you know how many teeth on the transmission drive??

 

I have always used the 8 tooth trasmission gear. Has worked for me.

 

genekend i have a 97 f150 with 255/70/16r and 4.10 gears.. what gear do need? can you help?

 

According to the calculator at http://www.finer.com/Internet/pages/speedo.htm you need a 22 tooth gear which I don't think they make. You might try a 21 tooth it might be close.