Gear Ratio

[CHP8336]

Originally Posted by SSPGARY

Is there an easy way to tell what gears are in my 89 AZ DPS car?
Thanks
Gary

The gear ratio tag is bolted to one of the bolts on the rear end cover.If the metal tag is not there then someone removed it. The way to tell from the outside of the car is to look at the tag and you will see a code like 3L.55 so that would mean 3.55 Ratio with a limited slip differential. If It is a non limited slip it will just list the ratio # without the L. If you have any other questions on rear axles West Coast Differential in Rancho Cordova Ca has a Great site that has just about everything you would ever need about differentials on there site. Rich

[28HopUp]

Considering the age of these cars, your gears could have been swapped out along the way and the tag lost. You could safely jack up both rear tires, and with it outa gear count the driveshaft revolutions for one complete rotation of the rear tire. With a t-lok, you'd find:

* just shy of 3 turns would be around 2.73:1 gears (depending on year)
* close to 3 turns would be 3.08:1
* 3-1/4 turns = 3.27:1 (or 3.31:1, depending on year)
* 3-1/2 turns = 3.55:1
* 3-3/4 turns = 3.73:1
* just shy of 4 turns = 3.90:1
* just over 4 turns = 4.10:1
* just over 4-1/4 turns = 4.30:1

For some reason, open rear-ends don't work with that method (they are half that). I need to read up on why that happens.

[SSPGARY]

Thanks for the quick response guys. I'll look into it today.

Gary