Thread: General Wheel Bearing Q

Originally Posted by amshaw

G'Day All,
Last week a had my front right wheel bearing die....just wondering is it best to do the other side aswell? I have the bearings to do the other side but thought I had better ask anyway.

Also is the old jack it up and wooble the rim trick still the way to chech the rear bearings while Im at it? Or is it best to take rim off and spin hub and wiggle that?

If I had a wheel bearing die I would check all of them! Better to leave the wheel on, spin and wiggle them using it, you have more leverage. Look for excess free play - there should be just perceptible free play, and no roughness at all. Another good check on the health of wheel bearings is when starting from cold, drive a few kilometres, preferably fairly fast, stop without using the brakes, and get out and check the feel of all hubs. They should all be the same temperature, and should be no warmer than any other part of the body. When travelling long distance, whenever I stop I always feel the hubs (including the trailer if towing) and make sure none are getting hot.

John

Originally Posted by JDNSW

If I had a wheel bearing die I would check all of them! Better to leave the wheel on, spin and wiggle them using it, you have more leverage. Look for excess free play - there should be just perceptible free play, and no roughness at all. Another good check on the health of wheel bearings is when starting from cold, drive a few kilometres, preferably fairly fast, stop without using the brakes, and get out and check the feel of all hubs. They should all be the same temperature, and should be no warmer than any other part of the body. When travelling long distance, whenever I stop I always feel the hubs (including the trailer if towing) and make sure none are getting hot.

John

Wise words thats all I can say.

yep at least pull the other side off and inspect them

i use same rule as with brakes & concerning wheel bearings always do the whole axle then you know all is ok on that axle

so yes do the other wheel bearing

The wheel bearings will love you, if you convert the seals to run the bearings in oil instead of grease.

The are are a few threads with the procedure.

IMHO, anything that has a matched component, or paired component should be inspected as required (time/distance interval or component failure) and if one part is faulty both replaced.... Im talking things like

wheel bearing sets (front axle/rear axle)
Tyres (front/rear)
UJ's (shaft sides)
Suspension rubbers
Brakes
Diff pinion seals (especially if its the front that was leaking)

its good preventative maintenace, forces you to check other things and generates usable spares.

I'd like to hear the science behind the "run them in oil" thing,,
bearings get hot, grease melts, bearings cool down
over full bearings will cause problems as theres nowhere for the grease to go except out.

Originally Posted by Pedro_The_Swift

I'd like to hear the science behind the "run them in oil" thing,,
bearings get hot, grease melts, bearings cool down
over full bearings will cause problems as theres nowhere for the grease to go except out.

Grease:-
Roller pushes grease aside and it stays aside until the unlubricated (and hence wearing) running of the bearing generates enough heat to melt the grease and it runs back and lubricates the rollers. Gradually cools until the grease sets, then the process is repeated. Eventually the bearings wear excessively, and sometimes may push the grease far enough away that it does not lubricate the rollers even when hot, leading to rapid failure. (more likely if there is not enough grease in the first place or if there is so much that the seal fails.
But the grease does not run out of the bearing altogether.

Oil:-
Roller pushes oil aside, and it immediately runs back, so that the bearing is never unlubricated and hence never gets hot (unless overloaded by too much preload) until -
Seal leaks and all the oil runs out, then the bearing overheats and eventually fails.


With either grease or oil, contamination with dust or mud will lead to rapid wear and failure, and contamination with water followed by disuse will result in rust, which will cause rapid wear when it is used again.
John