How to Replace Bearings for Mini-Suspensions
Axle and wheel bearing replacement is a common occurrence on small min-suspension vehicles, like ATV quads and trikes, as well as many ridin...

Axle and wheel bearing replacement is a common occurrence on small min-suspension vehicles, like ATV quads and trikes, as well as many riding lawn mowers and tractors. The bearing configurations are very similar on the ATV design, including such models as Polaris, Hustler, Max and the Argo. Most ATV rear axles have inner bearings held by a flange, while a front wheel will have a drum and inner hub. A DIY owner-rider can replace his bearings by using a few steps and basic tools. This article will encompass the removal and replacement of a front and rear bearing assembly found on common ATVs.
Instructions
Rear Axle
- 1
Apply the emergency brake on the vehicle and put it in gear. Use a socket and breaker bar to loosen the rear wheel lug nuts -- both wheels if you are replacing both sets. Raise the vehicle off the ground high enough to install two jacks under opposite ends of the rear frame. Finish removing all the lug nuts on the wheels. Remove the brake line with a flare wrench. Use a socket to remove the bolts holding the emergency brake cable, if so equipped.
2Look at the inside of the axle where it passes through the frame, and notice the small round collar which has an Allen set screw. Use an Allen wrench to remove the Allen screw from the collar. Use a hammer and thin punch to strike the untapped hole in the collar in either direction to free it up. Slide the collar back from the flange. Tap the outer wheel hub from behind with a hammer and pull axle straight out.
3Use a socket to remove the 3 or 4 bearing flange bolts. Use a screwdriver to pry the outer flange away. Reach in and pull the bearing and race (in one piece) straight out. Pack the new bearing with grease, if it has come dry in the package. Dab some grease around the inner flange and push the bearing and race into its seat. Replace the outer flange, along with the flange bolts, and tighten the bolts with a socket.
4Push the axle back into the flange hole, turning it back and forth until it seats firmly. If the axle shaft has splines, move it back and forth gently and push it in until it seats. Position the collar on the axle exactly where you took it off -- look for the small Allen screw mark on the shaft. Tighten the Allen screw on the collar.
5Place the wheel back onto the outer hub and insert the lug nuts. Partially tighten the lug nuts with a socket and breaker bar. Replace the brake line and tighten it with a flare wrench. Reconnect emergency brake cable and tighten it with a socket, if so equipped. Repeat the procedure on the opposite rear wheel.
Front Axle
- 6
Apply the emergency brake, and set the vehicle in gear. Partially loosen the front wheel lug nuts with a socket and breaker bar. Raise the front end of the vehicle with a floor jack and support it with two jack stands. Finish removing the lug nuts with the socket. Use a screwdriver and hammer to tap the dust cover off the end of the axle spindle.
7Remove the cotter pin on the castellated nut on the spindle. Use a socket to remove the castellated nut, turning it counterclockwise. Remove the spacer-washer and put it aside. Pull the brake drum straight out from the spindle end. Remove the inner and outer bearing from within the brake drum hub.
8Wipe the inside and outside races down with a rag and brake cleaner. Pack the new inner and outer bearings with bearing grease, if they have been packaged dry. Squeeze enough grease into the needle bearings with your fingers, until the bearing cages fill up.
9Set the inner bearing inside the race on the inside of the brake drum. Carefully align and push the brake drum back on the spindle. Place the outer bearing in the outer race and set the spacer-washer over it. Screw the castellated nut on by hand, then tighten it gently with a socket until the nut hole aligns with the spindle hole. Place a new cotter pin into the hole and bend the pin flanges with wire cutters. Tap the dust cover back on with a hammer.
10Place the wheel back on the spindle and insert the lug nuts. Partially tighten the lug nuts with a socket and breaker bar. Use the floor jack to raise and remove the jack stands. Finish tightening the lug nuts with the breaker bar and socket, using a crisscross pattern. If you wish, refer to your owner's manual for the proper amount of torque in foot-pounds required for your wheels. Use a torque wrench to tighten all the wheels to specifications, if your repair procedure includes bearing replacement on all the wheels.