I'm thinking about replacing my 3.90 differential in my automatic and installing the 4.10 diff from a manual. Obviously this would change the speedometer and odometer readings. Does anyone know if there is some existing dip switches or something to change the speedometer set up from auto to manual?

 

To change the speedo i believe there is a gear that you have 2 order and get changed. I could be wrong as i have no idea if this is the case with the FD but i know that when i was looking around for cherokees with lifts you had 2 order a new gear for it... Wouldnt changin the gearing mess up the automatic since it will be at a different rpm range when shifting?

 

order from dakota digital a black box (model dd-sig2 i think) that can intercept your speed signal and reconfigure it so that the speedo will read correctly. price is about $100.

 

Pomanferrari

Hi thanks for the lead on Dakota.

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