I'm going to swap out my 3.08's with 3.73's.......i have A40D? auto trans. and a superchip.....can the chip correct the speedo, or is there a gear in the tranny like the old days? I have heard both mentioned and wanted to make sure. If I have to have the chip reprogrammed, how do I get that done and what's the cost?

Any help would be appreciated........Toby

 

all you have to do buddy is go to your local ford dealership and tell them what tire size and gear ratio you are goin to and for about 20 bucks you will get a reduction gear that goes in the tailshaft of your tranny. thats how you fix your speedo

 

That part should cost even less than twenty bucks and the install is a five minute job. All you need is the right size wrench. I did mine in the Ford parking lot on my old '97. Be careful though, the parts guy at the ford dealership tried to sell me the wrong gear. I changed the speedo gear for larger tires so I don't know which way to go (larger or smaller number of teeth) for a lower gearing. Hope this helps.

 

Use this link to get an idea of what gear you need:

http://www.finer.com/internet/pages/speedo.htm