How do you re-calibrate the speedo after a gear swap. Is it done in the computer, or is there still a drive gear in the trans. Somebody told me you don't need to do anything, it picks up off the ABS sensors and adjusts itself.
On the SN95 models you either need to change the speedo gear or buy a speedcal from Dallas Mustangs. I just put in a DM speedcal on my 98 before I traded it it, worked awesome and was $100. You do need to install something, it will not figure it out on its own. If you have a 99-04 you can use either the Speedcal or an SCT/Diablo programmer to fix it.
Matt, the speedo gears are only accurate on 3.73s or lower (numerically)gears. Everything above (3.90, 4.10, 4.30...) requires a Speedcal or a computer flash. In the spring time, I'll be flashing my car with my new SCT2 tuner. After I do that, I will be removing my Speedcal.
I had 3:73's put in the car. I bought the red speedo gear and the speedo is where it should be. I went on a trip to Ct. last weekend. Mapquest said it was 159 miles, My odometer read 163 miles. I would say it is about dead on.
Sweet! Yes, with 3.73 the speedo gear will be pretty accurate. Did you notice much of a difference after the 3.73s were installed?
It is a very noticeable difference. Even my wife noticed the difference, and I did not tell her I did a ratio change.
Whoever told you that, don't pay them to work on your car. In fact dont even listen to them as they are stupid. The Speed sensors in the wheels(both FRONT and rear) correlate with the wheel speed on the abs rings at the hub and with the ABS system. How the hell the front wheels have anything to do with the final drive is beyond me. They have jack to do with the Output Shaft Sensor and Vehicle Speed Sensor in the transmission. A Speedcal will correct the speedo very accurately.
You could get speedo gears to compensate for 5.13 gears if you wanted to, you just need to change the drive gear along with the driven gear. :thumb:
