Swapping the gear set in your vehicle from a 3.73 to 4.10 ratio will provide slightly better acceleration, at the price of slightly worse fuel economy. While the exact procedure for swapping gears varies based on your specific vehicle, generally speaking it requires you to swap out the gear set in the rear differential. This requires removal of your rear brakes and possible removal of the rear axles, followed by removal of the rear gear set.
Park your car and use a hydraulic jack to raise the rear and place it on jack stands. Remove the wheels and then remove the rear brakes. The rear brakes will typically be held to the rear rotor with two bolts. Remove the calipers and zip tie them out of the way, making sure you are not placing any weight on the rear brake line.
Remove the C-clips that secure the rear axles, then remove the bottom bolts on the rear differential. Allow the fluid to drain out of the differential. Some vehicle may have dedicated drain plugs on the rear differential cover, in which case drain the rear differential via the drain plug. Expect anywhere from 1 to 3 quarts of fluid to drain from the differential, so be sure to have a pan to catch the fluid. Remove the rear differential cover by removing the securing bolts, which can number from eight to 12 bolts.
Remove the rear locking bolt with a wrench, then rotate the carrier for the shaft to slide out. Push in the half shafts to remove the C-clips and slide the half shafts away from the center carrier. Remove the carrier caps with a socket and long ratchet. Use a large pry bar to push the carrier up and release it from the housing. With the carrier out, you will be able to release the drive shaft by placing a punch in the locking position, then use a rubber mallet to push the pinion out.
Use a bearing puller to remove the old bearing in the pinion, and then press the bearing on the new pinion. Install the pinion with a new crush sleeve. Shim the carrier to make sure it is centered. Bolt the new gear into the differential and torque down the retaining bolt. Install the differential ring gear, making sure to shim correctly. Reinstall the caps and torque to your manufacturer's specifications.
Reinstall the axle and reinstall the C-clips into the differential, followed by the spider gear drive pin. Reinstall the differential cover with a fresh gasket, then fill the differential with fresh fluid. Be sure to slowly drive a few figure 8 patterns to assure fluid distributes properly.
