im hoping someone here can help me with this one. i have a 94 2wd flareside f150 5.0 5speed, its got 3.08s and goes down the highway like a dream, but it is a little lazy out of the hole. its got a few bolt-ons, a superchip k&n, underdrive pulleys, motorsport stainless headers, and flowmaster exhaust. it runs pretty good considering its a 300 inch motor in a heavy truck, but id like some better light to light acceleration and to be able to pull a little more weight( as much as the p.o.s mazda trans can take anyway). i noticed that vehicle speed sensor is in the differential and that the carrier has a reluctor wheel on it. my question is if anyone makes a limited slip diff. and if i change the ratio how will i callibrate the speedo. thinking of 3.73s or 4.10s since we use my wife's 03 crewcab for highway duty. i know that a gear change in mustangs make a huge difference but id like to know if anyone has done one of these swaps, especially with a maunal trans. any input is appreciated.

 

Well, you will notice a significiant difference in changing your gearing, especailly if going to 4:10's. The speedo gear that is on the ring gear will bolt up to your new gears and the limited slip shouldn't affect it. I changed from 3:55's to 4:88's and noticed a very big difference, but I was turning 35" tires. Just be aware that your speedo will be off. Hope this helps.