How "I" replaced my rear wheel bearings.

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pandemonium001
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How "I" replaced my rear wheel bearings.

Post by pandemonium001 »

Stripping the rear hubs is easy enough once you have done it,
I recommend breaking off the castle nuts while on the car.
a good quality impact socket and breaker bar or impact driver should get it. I measured it around 800Lb/ft to remove.

Remove the rear arm from the car

Heat is your Friend, propane gun or similar makes life a lot easier. and a vice is nice.
remove castle nut.
Heat the output flange (the one the wheel bolts to) and use a puller it will come straight off. dont try and hammer the shaft through!! the end will cave in and damage the threads. I learned the hard way, you will see in the pics later.
Now press or hammer(usung a sacrificial drift softer than the shaft) the shaft through the bearings.
remove the seals
Walk the bearings out the hub with a drift, you will need to move the spacer tube side to side to do this.

Do not loose the shim from behind the outer bearing

Keep all parts matched side to side the shims and spacer tubes may be different sizes

I measured mine and both shims where the same size so may just have been lucky.


clean clean clean

you should end up with this
Image

Measure your new bearings they should be the same thickness as the ones removed to within 0.1mm or so

heat the bearing housing
Image

Insert the inner bearing it should drop most of the way in
Image

If needed drive it down hitting only the outer race of the bearing until seated on the shoulder
Image

Insert the seal and push into place
Image

apply a little grease the inner edge of the seal once installed

Now you are tring to heat the inner race of the bearing to install the shaft
Image

heat down the center, the rubber seal stays fairly cool as its shielded by the bearing, the inner race take on a fair amount of heat and should be to hot to touch.
Image

now slide the shaft up through the bearing and give a light tap if required. You will see i had to machine the damaged bit of thread off my stubs to save them.
Image
Image

you need to fill the cavity with some grease, i found it easier to cover the spacer tube in it then slide it down.
Image

pack some more in
Image
it doesent need to be completely full just enough to lube the bearings

Now heat the housing again
Image

INSTALL THE SHIM

Ideally you want to either cool the stub shaft or heat just the inner race of the bearing so it slides down a bit easier.

I just heated the housing and slowly drove the bearing into place. Then pushed some more grease into the bearing.
Image



INSTALL THE OUTER SEAL

This is how i secured the shaft to the vice for tightening the nut.
Image

Ensure the splines are clean
Image

heat
Image

This time i went a little hotter "smoking" and the flange litterally dropped on.
Image

Run on nut and torque
Image

I went to 220lb/ft Max for my wrench, then pushed on a little further to line up with the locking holes. so probably ended up at around 300lb/ft.

Hope this helps anyone that wants to try it, any other suggestions are welcome.


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Peter V.
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Re: How "I" replaced my rear wheel bearings.

Post by Peter V. »

Nice workplan. Thanks.
Gr Peter V.

.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.

BMW E21, 1981 320/6 Ascot Grau.
BMW E85, 2004 Z4 2.5i Sterling Grau.
BMW F31, 2017 320dA EDE Luxuryline Mineral Grau.
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nas80
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Re: How "I" replaced my rear wheel bearings.

Post by nas80 »

fantastic write up.
[img]http://s13.photobucket.com/albums/a285/nasbucket/forumsig.jpg[/img]
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e21-Mark
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Re: How "I" replaced my rear wheel bearings.

Post by e21-Mark »

Nice work, as ever. :thumbsup
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Jeroen
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Re: How "I" replaced my rear wheel bearings.

Post by Jeroen »

I second that! Going straight to the Top Tech Topics. Thanks man!
Regards/groeten, Jeroen
niske
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Re: How "I" replaced my rear wheel bearings.

Post by niske »

One thing only… dust cover plate should be mounted before flange…
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