Testing a wheel hub for failure Topic is solved

Post by **FireFox31** » 21 Mar 2023, 23:23

Is there a clever way to check a wheel hub with a stethoscope while the wheel is off the ground and moving? I put my 2000 V70 automatic on a lift, removed both front wheels, and started the car. In Neutral, the right wheel spun but the left did not. I put it in Drive and gave it a little gas but it felt like there was a problem, so I quickly stopped. Seems like the differential isn't able to do its job of making both wheels go forward. I want to hear the left wheel moving. How could I make the left or both front wheels spin at the same time while up in the air? Thanks.

Post by **abscate** » 22 Mar 2023, 00:36

You tie down the other wheel with a short piece of rope, or line, as sailors say. The differential will always spin the wheel of least resistance which is how you get stuck with one wheel on ice, sneers from AWD aside

My experience. I’ve done about 10 wheel hubs on P80s. I have not found a reliable bench test to tell a bad from a good bearing. Failures seem to be at about 150k in my four season climate , but if you move to Iowa they don’t fail , ever

Post by **volvolugnut** » 22 Mar 2023, 06:55

If one wheel turns and the other does not, the wheel that doesn't turn has more resistance. This could be dragging brake or bad bearing. As said above , tie down the turning wheel and listen.
Volvolugnutm

Post by **erikv11** » 22 Mar 2023, 09:46

Move to Iowa!

I've now replaced a couple P2 front hubs due to failure, just not any P80 ones. Although I have a bad rear hub bearing on the 95 right now, so the streak is over.

Post by **FireFox31** » 22 Mar 2023, 13:10

This seems risky to tie a wheel. With the wheels off the ground and the car on in Neutral, should I see one wheel spin forward and the other wheel spin backward? How much effort is required to stop one or both wheels from spinning in Neutral? I gently tried to stop the spinning wheel and it didn't slow at all.

What could I tie the spinning wheel to? I'm nervous that it would have a lot of rotational force and get the rope all tangled up. Tying it to the car body seems like it could rip off that part.

Perhaps the fact that the one wheel is not spinning and I hear a slight growl is enough to replace the hub.

Post by **abscate** » 22 Mar 2023, 18:00

You can actually just stop it with your hand but a tie off is safer. You won’t feel engine torque.

Post by **volvolugnut** » 22 Mar 2023, 18:18

First question: Is this a car that you recent drove and you suspect a hub problem?
If yes: Then leave the turning wheel on the ground, set the parking brake, raise the other wheel off the ground, start engine, and place in drive. There should be little resistance to the other wheel turning and very little torque applied to the wheel on the ground. Chock the three wheels on the ground if you are nervous.
If not recently driven, Raise the suspect wheel, place in neutral, and try to turn by hand. It should turn but may be hard if brakes are dragging, bearing is bad, or other damage. Listen for noise and try to identify.
Don't try to stop a turning wheel by hand. Risky business.
volvolugnut

Post by **foggydogg** » 22 Mar 2023, 18:36

It's hard to get a hub bearing to growl if it's unloaded - unless it's really toast. I heard of a guy who put a cell phone in a freezer baggie, wire tied it to the lower control arm, hit vid record, and went for a ride.
Brake pads rarely exert the same force on both wheels; maybe try using your favorite method to pry the pads away from the wheel you want to see spin. As mentioned above, power goes to the path of least resistance.

Post by **abscate** » 23 Mar 2023, 01:51

Above, indeed if you turn a front wheel on a car with both up in the air, the other wheel will rotate on the opposite direction. This is a result of the differential gears.

With the car in park , the drive pinion is frozen, denoted by X

The differential pinion reverses the rotation of the axle shaft to the other wheel as shown here

Post by **cn90** » 26 Mar 2023, 11:56

1. My lazy way:
- Jack one wheel up (chock diagnonal wheels first!).
- Put car in Nutral.
- Use a long screwdriver and push the brake pads a bit so they don't contact the rotor.
- Now spin the wheels and listen for noise.

2. The correct way:
- As above but remove wheel, then remove caliper and hang it to the coil spring.
- Re-install the wheel and just snug the lugs, no need to tighen the lugs.
- Having the wheel on make it easier to spin (from the inertia of the wheel).

As abscare said, wheel bearing lifespan is about 140K-200K.

If you submerge the car in flood water, such as trying to drive through a deep puddle,
the lifepsan is significantly shortened.