viperbob

It was a disasterous day at Thunderhill. I could not run at all because when I was giving the car the final go over I noticed that the front Mich. Pilot cups were down to the cord all the way around on the very inside inch of the tire. While all treadwear indicators were still above the minimum and I had checked the tires before leaving the house 175 miles before the journey. So 2.5 degrees of negative camber is REALLY bad for Mich Pilot Cups.

OK, so being in the middle of no where, I needed to find 2 18" tires just to get home. Finally after numerous calls to tire centers, I found just 2 located 30 miles away. Bling bling for your pickup was the order of the day at the Les Schwab Tire Center in Orlind. Anyway, at some point while I was taking the fronts off and on myself and continually telling the 18 year old kids with air guns to get away from the car, one of them must have loosen the left rear (I had just re-torqued the wheels at the track). Why? I can not figure out.

So what happened? 50 miles down the road my left rear starts shaking. Thought it might have been a flat. Pulled over and one of my lugnuts and the stud were gone. The other 4 were loose and the wheel was not seated on the hub any longer. Tightened the 4 remaining and made it home with no problems.

Now the tough part. I need to remove the rear wheel hub in order to press the old stud remnants out, and the new one in. My impact gun was able to remove the 32mm drive axle nut torqued to 379 Lb Ft. I even used a puller and was able to push the drive axle in a little to loosen it from the hub. But how does the hub come off???? Is it pressed into the wheel bearing? The manual says nothing about this procedure anywhere. Any help would be appreciated.

Thanks

viperbob

Thanks Kim. Yes a minor drag, but a drag none the less...

OK, now this is coming back to me from my 911 Carrera days. The hub tends to weld itself to the wheel bearing. After X time when you try to take off the hub, you destroy the wheel bearing. The way to remove it is to unscrew the 4 bolts that hold the wheel bearing. Backing these out equally forces out the wheel hub from the bearing or it will destroy the bearing on the way out. Pretty much when the bolts are ready to fall out, the hub is off.

So the outer race of the wheel bearing is now stuck on the end of the hub. I'll try to see if a machine shop can remove this, but the brain cells that are starting to fire remind me that I had to cut this off the first time it was removed on my Carrera.

Darn good thing I still have my handy dandy factory wheel bearing tool. Looks like I'll need it after I remove the axle....

Tom W

I had planned an email to see how the Black Beast did, now I see it will not be necessasry. Sorry to hear of the difficulties.

DJF1

Wow...terrible thing that happened there!!! Good luck to you Bob!
BTW -2.5 is not bad on MPSC's. I have very even wear on all 4 corners and I'm up there on the negatives. Difference is that I do not drive on the track on them as I pressume you do? Otherwise try to find a temp meter and see what kind of temps you are running. if you have more than 12-15 degrees of heat difference between the edges then you needs to adjust your air pressure.

viperbob

As I explore deeper, apparently the Porsche Engineers were aware of this problem taking the hub off and destoying the bearing, so they even left relief for a 2 jaw puller to remove the bearing race from the hub.

Here is a photo of the hub and the bearing assembly in the car. You can see the broken stud in the photo.









Well as long as the back end of the car is up in the air, and I have to remove the axle from the tranny I guess I will also be doing an RS Tranny mount installation trying out the wheel bearing tool. Looks like it will work. This I will take pictures of for a DIY.

chris walrod

Try to heat up that inner race itself, also maybe put the hub in the freezer before heating up the inner race. Should help you get that off with a puller. Last resort would be to cut that thing off like mentioned earlier.
Good Luck!