Adjusting Your Rear Wheel Bearings

This is an adjunct to the "Painting Your Calipers" write-up. If you decide to paint your calipers, then you may as well check your wheel bearings while you’re there! However, this procedure can be done any time you jack one of the rear wheels off the ground—whether it be to clean the area, to change or rotate a tire, or to do any brake work.

"So why do I want to check the bearings?," you are thinking. (See the diagram below) The bearing is the roller that is inside the wheel hub. The wheel actually rolls around the bearing. The bearing needs to be snug, but NOT too tight. A loose bearing will cause additional "play" within the hub. This means the wheel’s rotational axis can shift around a bit and this throws off the steering and handling geometry. This will also cause additional wear to the bearing. Conversely, a bearing that is too tight could potentially cause enough extra friction to limit the wheel’s rolling friction. This could lead to increased bearing temperatures and bearing failure.

Tools Required to check the bearings = a jack and your own hands.

Additional tools required to make the adjustment (IF NECESSARY) = wheel nut wrench (see the "What’s in your trunk [boot] section"—J.K.), needle-nose pliers, flat screwdriver, and a Torque wrench (optional).

Check Procedure:

• Jack up the car so one of the rear wheels just rises off the ground.
• Check the wheel bearing’s "play."

To do this, grab the tire with both hands, one on each side of it (top & bottom or forward & rear sides). If it is solid (without play) then you are done and your bearing is adjusted fine. If you can shake the wheel and feel play in the bearing, you should then proceed with "adjustment."

Adjustment Procedure:

• Remove the wheel—put a paper towel between the tire iron and the lug nut to avoid scratching it up
• Set the wheel aside— to avoid scratches be careful NOT to set the outward painted surface of the wheel on the ground!
• Marvel at the up-close viewing of one of the world’s most incredible suspension set-ups!
• Check your brake pad and rotor condition while you are here.
• Use the flat-end screwdriver to pry out the dust cap from the hub center.
• Using the pliers, remove the securing split pin from the nut.
• With a socket torque wrench, tighten the hub nut to 18 lb.-ft. (25 Nm) WHILE rotating the wheel—this is the step that snugs up the bearing!
• Loosen the nut and then re-tighten using only fingers to "finger-tight."
• Insert the securing split pin. If needed, turn the nut the smallest amount further to allow re-insertion of the securing pin through the nut. Bend the short end over the nut and the long end over the end of the axle.
• Refit the hub dust cap and replace the wheel.
• Check the bearing’s play again to be sure you did the right thing and feel the difference.

Because you are tightening the bearing nut and then loosening it to a final position of only "finger tight", you can see why a torque wrench is not absolutely necessary—just be careful! My bearings were fine, but Steve P. said he needed to adjust his. He said it made a noticeable difference in the play of the bearing and handling of the car.

Happy Elan-ing,

Doug (av8ndoc@aol.com)