Gear install
Tools needed; Lift or jack stands, impact gun, heavy duty socket set with long extensions, PB blaster, mallet, bearing
press, pry bar, and Micro caliper.
Gear set should include ring & pinion, shims, crush sleeve, friction modifier, rear end bearing kit, 2-3 quarts of gear oil.
1. First place the car in neutral, and the E brake off. Chock the front tires, and either jack the car up, or on the lift.
2. Remove both rear wheels, and remove the brake calipers, rotor clips, and rotors.
3. Then remove the driveshaft from the rear pinion. Then open the rear end cover and drain the oil( this will have a foul
odor in most cases).
4. Once the oil is drained remove the c clips & rod that allow the axles to slide outwards. Remove the U bolts that hold the
differential in place, and pull on the differential( this should take a little bit of pressure and not just fall out).
. Once the diff is out remove all bearings, shims, carriers, and the ring gear off the diff. Then remove the pinion gear, race
bearing and carriers.
6. Take brake cleaner and thoroughly clean the rear housing, and differential.
7. Now you can either measure the entire rear to get the proper shim or, you can shim the pinion gear and measure it that
way with a micro caliper.
8. Install the pinion gear with race bearing and outer bearings.
9. Install the new bearings, carriers, and ring gear on the diff. and install that and shim to proper specs. test the wear
pattern, by adding shims for pinion depth, and for checking backlash. This will take the longest, and must be done
correctly for a long lasting rear gear.
10. Once the wear pattern is good remove the pinion gear and slide on the crush sleeve, and tighten down the pinion
gear, and install the diff, and u bolts. Double check wear pattern.
11. Reinstall the axles, c clips and rod, and rear end housing, driveshaft, rotors, rotor clips and brake calipers, and
wheels. Then add enough gear oil and the entire bottle of friction modifer(Ford modifier is the best) until you feel the fluid
with your finger.
With this your speedometer will be off, so you need to correct this. For 1994-1998 Mustangs you can use a speedo gear to
correct this up to a 4.10 gear. Anything steeper will require a DMP Speedcal (best) or an Abott ERA. For the 99+ Mustang
you CAN NOT use a speedo gear. If the car is an automatic (manual will not work), then a chip can be used to correct this.
They say you should give the gears at least 3 cycles of warming up and then cooling down( roughly 25 miles) to establish the wear
pattern before you decide to get on it. If you don't the gear will not cure and will become soft, causing troubles down the road.
Tools needed; Lift or jack stands, impact gun, heavy duty socket set with long extensions, PB blaster, mallet, bearing
press, pry bar, and Micro caliper.
Gear set should include ring & pinion, shims, crush sleeve, friction modifier, rear end bearing kit, 2-3 quarts of gear oil.
1. First place the car in neutral, and the E brake off. Chock the front tires, and either jack the car up, or on the lift.
2. Remove both rear wheels, and remove the brake calipers, rotor clips, and rotors.
3. Then remove the driveshaft from the rear pinion. Then open the rear end cover and drain the oil( this will have a foul
odor in most cases).
4. Once the oil is drained remove the c clips & rod that allow the axles to slide outwards. Remove the U bolts that hold the
differential in place, and pull on the differential( this should take a little bit of pressure and not just fall out).
. Once the diff is out remove all bearings, shims, carriers, and the ring gear off the diff. Then remove the pinion gear, race
bearing and carriers.
6. Take brake cleaner and thoroughly clean the rear housing, and differential.
7. Now you can either measure the entire rear to get the proper shim or, you can shim the pinion gear and measure it that
way with a micro caliper.
8. Install the pinion gear with race bearing and outer bearings.
9. Install the new bearings, carriers, and ring gear on the diff. and install that and shim to proper specs. test the wear
pattern, by adding shims for pinion depth, and for checking backlash. This will take the longest, and must be done
correctly for a long lasting rear gear.
10. Once the wear pattern is good remove the pinion gear and slide on the crush sleeve, and tighten down the pinion
gear, and install the diff, and u bolts. Double check wear pattern.
11. Reinstall the axles, c clips and rod, and rear end housing, driveshaft, rotors, rotor clips and brake calipers, and
wheels. Then add enough gear oil and the entire bottle of friction modifer(Ford modifier is the best) until you feel the fluid
with your finger.
With this your speedometer will be off, so you need to correct this. For 1994-1998 Mustangs you can use a speedo gear to
correct this up to a 4.10 gear. Anything steeper will require a DMP Speedcal (best) or an Abott ERA. For the 99+ Mustang
you CAN NOT use a speedo gear. If the car is an automatic (manual will not work), then a chip can be used to correct this.
They say you should give the gears at least 3 cycles of warming up and then cooling down( roughly 25 miles) to establish the wear
pattern before you decide to get on it. If you don't the gear will not cure and will become soft, causing troubles down the road.
