Spedo shuts down the truck

[Ridiculousness]

Alright so I have a 2000 Ford Ranger 4x4 regular cab and this is killing me. so I bought a (gem) 4x4 module off ebay because mine was not engaging the 4x4. I just replaced it and now when I drive the truck the speedometer reads 140km/h when I am really doing about 10 km/h. As soon as the truck hits 160 km/h (really 15 km/h) the truck shuts down. Any guess on how to fix this. Can I recalibrate the spedo? Is it a bad 4x4 module?
Some other information I ran the truck around the block without the GEM (4x4 module) it worked fine just didnt have wipers, 4x4 ect.... Also I put the old (gem) 4x4 module back in and the spedo works fine. Also I havnt tryied it yet but I was thinking of just disconecting the speed sensor but would like to have a spedo.

 

[adsm08]

Well the new module should get programmed when installed, and that could be at least part of your issue.