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Drive wheel bearings, how do they work?

I know this is a sort of… newbie question, but how do drive wheel bearings work? I think I know how non-drive wheel bearings work, since they really don’t have a shaft that spins as in the drive wheels, but I’m sort of unsure about drive wheel bearings. I know where the bearings are located, and I know how a bearing works, but I’m not sure what the purpose of a drive wheel bearing is, because from what I understand, the axle is still directly paired to the main wheel hub, but the bearing just sort of makes a smooth surface for the axle to run through? A diagram would be appreciated!

Google FWD bearing cutaway, click on the images tab. There are drawings there. Typical bearing designs these days are 2 rows of angular contact ball bearings pressed into the knuckle or built into a bearing and hub assembly. They do the exact same task on the driven axle as they do on a non driven axle.

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There’s just a lot to consider on that issue

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Ok, I might understand this. So, the bearing really has nothing to do with the axle itself, it just sits where the main hub is, making sure that the axle can rotate freely without any real resistance. I thought the bearing was inbetween the axle and the wheel. I think I understand this now

Study the various methods of attaching the wheel to an axle in the link. The bearing is between the axle and wheel on quite a few but totally separate on others. There is no simple answer.

Yeah, I read about the full-floating vs semi floating systems, and I’ve also seen how the axle can extent to the wheel, or it mounts to the bearing inner race or even goes farther out to the wheel itself. They’re all generally the same though, right? (with a bearing that connects to the axle and to the wheel hub)?

The bearing goes between the knuckle and the axle. The knuckle is the fixed, non rotating part that is attached to the vehicle through the ball joints and control arms. The axle goes through the middle of the knuckle. The outer race is attached to the knuckle, the inner race attached to the axle via the hub. The ball or needle bearing allow the axle/wheel to turn smoothly while the knuckle holds the wheel in place in relation to the vehicle.

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It really doesn’t make a great deal of difference to the bearing if the wheel is driven or not . The non driven wheel rotates on the axle, the driven wheel rotates with the axle. In both cases the bearing allows free rotation between the axle and hub. A gushing would work also but would have more drag and wear out much quicker. You can see the difference in cheap lawnmowers with bushings and expensive ones with bearings. The expensive ones push easier and smoother.


Yup, thats what I was wondering. Thanks for the help, sorry if this question was a sort of newbie one :flushed:

No worries, we were all newbies once upon a time!

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When I bought my first car , a $20 dollar, 52 Plymouth, I knew nothing about cars. I had replaced a head gasket on a 47 Fraser but that was under my stepfathers supervision. The only reason I was doing it was because I had blown it the day I got my learners permit at 16. I had been driving for 4 years but very cautiously because I did not have a license. Once I got my permit, all bets were off.

I was replacing the 52 because cold weather was coming because the rocker panel, Bottom of B pillar and all the floor outside the frame rais were gone from rust.

I was going to pick up the next car and the 52 started overheating and I stopped at my wife’s parents house to fill the radiator with water. The engine was very hot, the water was very cold and I heard a sharp ping and water and oil poured out of the block.

I was standing there looking puzzled and wondering what had gone wrong and my mother in law walked out of the house, tool one look and said “where is your fan belt?”

LOL, I know a few things about cars now, but last year when I bought my first car, I didn’t even know how the camshafts worked. Luckily now, I’ve done a decent amount of research and if I get another car soon, it’ll probably be really easy to work on since I know a lot more than I did last year.

You will see the difference that you may have confused yourself with by looking o line for cutaway drawings of say a FWD axle and wheel bearing… and then comparing that to a solid axle (“rear end”) and how its bearing interfaces the internal axle. A vehicle to look up would be say a 90’ Mustang with a solid rear axle or a 80’s-90’s Ford F150… a 80’s-90’s Camaro etc… There are plenty other examples of vehicles that have a solid rear, so… Solid rear axle is what u need to compare to but I think you probably have it all worked out

…and there are no stupid mechanical questions. The really stupid ones are the ones who think they know and are too proud to ask… and waste no time really tearing things up and breaking things. Never be too proud to ask.


I think what I was thinking was that the bearing was an attachment where the axle would meet up with the wheel, I’m not sure exactly where I got that idea, but I think I know now how the bearings work, how they are mounted, etc. I did look up solid rear axles and surely enough, its basically the same bearing idea, just with the axle being solid instead of split like in a FWD car.
And btw, I won’t try to ask too many questions on here (to prevent clogging up the forum lol), only the ones I need help figuring out.

On the contrary @arwcca_166186 ask away… you wont clog up anything.

The purpose of a forum like this is to ask any and all the questions you like. I never really encountered any stupid mechanical questions but I have witnessed some silly superstitions and or half truths in the mechanical realm… so ask those questions as that is how we get rid of those types of things.