BruceWard

I finished up my brake job and the rebuilt calipers, new pads and new rotors feel great! Also the new clutch feels good.

But I have a nagging question in the back of my head, how do I know I adjusted the front wheel bearings correctly? The races, bearings and seal were replaced in the front hubs. I tightened the nut until I could not move the washer then backed off a 1/4 turn and could move the washer a little. Does this sound right? Can anyone give me tips on how to shake the wheel to feel for vibrations? I am missing the magic hands.

Phil Harrison

Bruce the workshop manual says:

"Tighten the clamping nut slightly while turning hub at the same time

Slacken clamling nut until finger pressure applied to a screw driver is just enough to move thrust washer. Do not rest screwdriver on hub."

I think you may be a tiny bit loose, but unless you get any shimy I'd leave it alone.

RajDatta

Bruce I have a shimmy that I get at very high speed stops as well, so this would help me as well. Let me know what worked for you and will give it a try on my car as well. What kind of bearing grease did you use?
Phil, I will give that method a try.
Thanks.

BruceWard

Phil, I should have said that I was using a screwdriver to push the washer. My question really hinges on the definition of just. After going for about a five mile test drive I tried pushing on the top of the wheel and it felt like there was some play when rocked. I tried the same on the rear wheels and the wifes car and they felt more solid. There was no vibration when driving but I think Ill take the hub caps back off and check the washer again.

I found a method of getting those hub caps off that works for me, where there is a gap in the hub close a pair of vice grips tightly on the cap. Then hit the vice grips from behind with a hammer until you have enough room to work the cap off with a screw driver, or it falls off. It helps to work around it in a circle.

Raj, I used Kendall Super Blue on the front wheel bearings and Swepco 101 on the rear CV joint I repacked. The advice I have been given is to clean up the races and bearings to check their conition and then to replace them if they are anything other than a mirror finish. I found discoloration (brown tint) on the bearings and one of the races had spun in the hub. The cost of the bearings and inner seals is around $40 (Paragon) and with the right tools ($12 at harbor freight) pretty easy to change out. You need a brass punch to knock out the old races without damaging the hubs and then a bearing insertion tool to put the new ones back in. The bearing insertion tool has a handle and little discs that match up the races so you can pound them in evently with a hammer. Before inserting the races put them in the freezer, overnight if you can and put the hubs in the oven for an hour at 250 to heat them up. Be careful to keep track of which bearing came with which race. When the races are cold and the hubs are hot they go together without damaging either.

I cheated by going to a friends house who had a 12 ton press ($100 harbor freight), took the races over there in an ice chest and put the hubs in the preheated oven at 450 for about 20 minutes. Then used the press along with the bearing insertion tool discs to push them in. It was very easy!

RajDatta

Hmm, interesting. I will have to check all this out next time I work on the car. Thanks for such detailed instructions. I might drop you a line at some point.

Phil Harrison

" My question really hinges on the definition of just"

Yes there's been that discussion on the main 944 board... kinda like the manual way of setting belt tension "twist 90 degrees with finger pressure"...

Sounds like you're good to go though.

BruceWard

Well I found the problem, the drivers side front wheel bearing was not sufficiently tightened. It had been tight before the test drive, but I guess the bearing found some more room during the drive. I took the cap back off today and was able to turn the locknut two - three additional turns.

I talked to a Porsche mechanic who has done a lot of wheel bearings and he suggests leaving an allen wrench in the locknut and using the allen wrench to turn the nut. That would cause the hub and rotor to be turned as the locknut is tightened. Both the turning of the hub and the additional leverage will help ensure that it is adequetly tightened.

By the way the allen bolt in the locknut is a 6mm.

BruceWard

I drove about 70 miles today and I highly encourage everyone to change their wheel bearings! I detoured over a couple of mountains with 180 degree plus turns and found that the car felt much more solid and precise cornering, which previously I had thought was impossible. This is $40 and a couple of hours you really should spend on your 968.

Raj, just for you I verified that there was absolutely no vibration up to 120 MPH. Where does your vibration begin? I doubt there is any vibration above 120 but since Im breaking in the clutch and brakes I decided to back off.

User 41221

Bruce,

Didn't you get snow down there? We have gotten WAY too much of the white stuff here...

Glad to hear you are back on the road!

Regards,

BruceWard

Nope, no snow down here south of the Ozarks!

We did have some sleet the other day! I would like some snow.

The T-Belt was easy, the clutch wasnt too bad, but the caliper rebuild was slowwwww! Its back on the road and driving better than ever now.

I may have to do some higher speed testing for Raj though.

Jay Wellwood

Hehehehee.....

RajDatta

Bruce, my only problem has been when coming down from a 150plus with very hard braking(Remember, I get there a lot quicker ), I get a slight shimmy that is not present if I use the pedal a little softly. I know for a fact that the rotors are not warped as they are very new and same for the pads. I checked the tierods for play and didn't find any. It can't be the control arms as I have zero deflection with Charlie arms.
Two things that I can think of are play in the strut tower and bearings. The bearing idea came from your post so thank you on that. I might just go ahead and repack the bearings and swap all the pieces out. Please send me an email with all the parts required.
It is impressive that you rebuilt your calipers yourself. Kudos on that.
Regards.
Raj

BruceWard

Ill post the part numbers here as well for future reference. I ordered mine from Paragon, they were not a factory part but seem to work just fine. Chuck at Paragon was a lot of help with my rotors / pads / rebuilt calipers project and when I asked for wheel bearings knew the partsI needed, both Chuck and Jason own 968s. Kirk at Zims and the guys at Sunset were also very helpful.


The part numbers, per PET, are

999 059 061 00 Inner Front Wheel Bearing
999 059 089 01 Outer Front Wheel Bearing
477 405 641 Front wheel seal


The numbers and prices from Paragon are

183576 (5B5) Wheel Bearing Front $11.41
000.981.63.05 Outer Wheel Bearing $11.24
477.405.641 Fr. wheel seal $3.790

You need two of each, you could replaceAnd you need some grease to pack them with.

It is tempting to put the new bearings in the old races but dont do this! The old races are just as worn as the new ones and the bearings and races are matched so make sure to keep each bearing with its race.

Also dont freeze the the new bearings, it will cause them to condensate moisture and you really dont water in there, and make sure you clean off as much of the old grease as possible both to make sure no impurities are left in there and so you dont stink up the kitchen!