mark944turbo

Tomorrow I am going to attempt to replace the rear wheel bearings with the trailing arms still on the car. Has anyone done this before? Any tips?

Today I removed one bearing by banging the center of it out from the transmission side, over the snap ring. Then I removed the snap ring when the hub was out of the way. Is there a different method to remove them? Like punching them out from the wheel side (meaning they fall out transmission side)?

Actually all i am trying to do is put different lug nut studs into the hub, but it looked like I had to remove the wheel bearing to get the hub off the car.


I tried to bang out the races but no luck. Ill try torching them next time.

TIA

Joe Jackson

Actually, I believe that you can replace the rear studs by removing the park brake assembly and knocking the studs out of the hub. I have yet to try it but I remember realizing that it could be done that way when I did one of my rear wheel bearings and removed the parking brake b/c I thought I had to.

But, now that you knocked the inner race out of the bearing, you'll need to replace it anyway. The proper method for removing the bearings is using a puller along with heating the trailing arm (though I've done it without heating with no ill effects). The puller you need to use isn't one you'll find at Sears or any other hardware store though. I believe a few Porsche sites sell one that will do Porsche rear wheel bearings. I have a set meant for doing front wheel bearings on front drive cars but it also works on 944 bearings. Do a search in both the turbo forum and 944 forum and you'll find pictures of the different styles of pullers. Do not try to hammer the bearing out as you'll do a lot of damage.

The bearing comes out the trailing arm away from the car only. There is a dead stop in the trailing arm preventing it from going in towards the transmission.

For reinstallation, just heat the trailing arm up and the bearing will drop right in, provided you insert it straight. I've gotten them stuck a few times and had to pull it back out then reheat and drop it in again.

mark944turbo

Well, I hope that I can get the studs out without removing the hub. What I am doing is switching to shorter studs off a parts car because I do not want to use the larger wheels that the PO had. Luckily I have only touched the parts car so far.

One thing I still dont understand is how to remove the snap ring before pulling the bearing out. It is covered by the hub until the hub is pulled out, and to get the hub out you have to remove the bearing. I think...

mark944turbo

"Using a soft drift and hammer from the inside of the trailing arm, drive the rear hub out of the trailing arm. " Clarks Garage

I guess it is possible to remove the hub without removing/destroying the center of the bearing. Mine just was stuck together too good.

I dont see the difference between hammering a huge socket of perfect size against the back of the old bearing and using a slide hammer. As long as I hammer carefully im assuming I wont do any damage. Is there more to this than Im seeing?

Joe Jackson

You will need to drive the hub out of the bearing which usually takes the inner bearing race with it. Then, you can remove the big snap ring and pull the rest of the bearing out. I've used a 24mm socket (I believe) to drive the hubs out although a slide hammer and hub puller is the better method.

mark944turbo

Thanks Joe, your advice is sure to help tomorrow.

slim_boy_fat

Cont forget to stick the bearing in the freezer overnight

Joe Jackson

You know, I found heating the arm much more effective than freezing the bearings. Then again, I only had my bearing in a standard freezer not the cool environmental chamber types that can go down to -60 F degrees. Those might considerably shrink the bearing. For me, just heating is all that's been necessary.

slim_boy_fat

No doubt, the alloy will expand much more then the hardend steel of the bearing, i was suggesting it it run in parallel with heat, not instead of!!

Joe Jackson

Oh, I know you were not suggesting to just freeze it. My point was that if he did forget to freeze it overnight, or if it didn't go in the first time, then he didn't have to wait around another day trying to freeze the bearing.

Danno

"I hope that I can get the studs out without removing the hub."

Aren't you gonna take the hub out to replace the bearings anyway? If you were only going to replace the studs, you can do that by pounding them out through the hole in the A-arm for the parking-brake cable (remove parking-brake mechanism and cable first).

Bones944

I just replaced my bearings last week. You can't remove the hub without destroying the bearing, as the inner race stays on the hub. You can remove it with a 2 leg gear puller. I have the Sir Tools bearing puller and it makes the job extremely easy. You could make your own to drive the bearing and hub back in using a long threaded shaft and round plates of the correct dimensions, but it may be difficult to find platesor large washers strong enough. Might stack some large washers though.

Van

I borrowed the Sir tool from a friend and started tackling the rear bearings.

In about 3 hours, I got everything apart and the bearings out (and the races off of the axles!) Now I just have to clean everything and then put it all back together.

xsboost90

i just use a bearing press and an impact - takes about an hour an axel.

APKhaos

At great risk of sounding like a Cassandra........but my car was completely destroyed [tub] when a rear wheel bearing collapsed on track. There is more than one way to f up the bearing install which can mean a major failure not far down the road.

Use the Sir tools [borrow/rent/whatever] and do it right. Fer crissake don't whale on the hub with a hammer to remove a bearing! With the Sir tool the old bearing comes our easy and the new one goes in nicely aligned and smooth as butter. No abuse required, and no bearing damage done.