Viperbob1

Like in the CV joints we use Krytox 217 in the bearings. $300/lb is a little expensive though for most budgets. But if you launch a space craft, this is the stuff you want on it.

AudiOn19s

Follow up:

Everyone that tracks their car should consider this a 2-3 year maintenance item and plan on replacing accordingly.

Both my drivers side bearings were bad which is understandable since we generally run clockwise tracks here in the US. But the passenger side ones weren't exactly "fresh" either just not to the point of making noise yet.

This one will go on my list again and get done after the next two seasons.

FWIW as a data point this is on a car that does 5-7 events per year and only ever runs on Nitto tires not super sticky rubber.

The new set was packed with NEO HP800 grease to see if it adds any longevity.

**edit...for those who are going to remove your own hubs like I did for this job**.

Ball joint separator is an absolute must. and stay clear of the ball joints when using the tool...they come apart with a BANG

e-brake sucks to take apart....take lots of pictures.

Front hub can be off the car in 20 min each pretty easily, rears more like 40-45 min if you take your time on the e-brake.

Torque spec for the axle nuts is 340 ft/ lbs...my electric impact pulled them off with ease?????

TomGT3

Thanks, did mine because of this thread. 60 track days (on NT01) and 35,000 miles.
My mechanic said that they were just starting to go.

He did not want to take the sealed bearing apart to replace the grease. How hard is it to separate a sealed unit?

JohnPG

Agree with this^ I've had one go at WGI, last year at Calabogie there was one 6-3 and two caymans had bearings go. Nothing worse than being at the track and having something like this shut you down.

Another item to consider are your axles. While ours with a close to stock ride height aren't as stressed as much as the cup setup, they still could and do fail after heavy track use. I'm replacing mine every two years. FWIW

Cheers

AudiOn19s

I'm struggling with that decision now. Car is officially on stands for the winter.

JRZ's are getting refreshed
Couple of loose monoballs are getting replaced
Exhaust coming off to clean up a couple welds.
Couple alignment tweaks being made.

...but axles are SPENDY!!!

I saw your posts and the posts in cup car land about servicing them. I'm not afraid of much but they seem daunting to service.

cfjan

The Turbo axles will fit and are stronger, right?

993GT

axle angles aren't necessarily a bad thing unless you are running out of available flex/angle...grease flows better with angle...service regularly and be happy...
original axles here with a nasty (P.O. installed) 'race' clutch and double the torque...

993GT

Should fit although PET says different #'s, I have no documentation ATM if stronger

AudiOn19s

The point here is you can't service the outer cv joint on the factory axles without machining and modifying the housing.

serickson

Andy I would be interested in what tools are needed to replace the wheel bearings. Did you just follow the workshop manual?

993GT

Hey Andy, you should be able to remove the CV boots, clean out the old grease and re-pack, really the only servicing you can do for CV's without a true rebuild/machining.
I'll be doing mine over the winter 'break'

JohnPG

Andy,

Did my JRZ last winter, I have them on a 2 year schedule. Yes the axles are pricey, but a failure could be potentially more costly. The CV joints could be repacked, but my main concern is metal fatigue. You figure 25 to 30 days a year. Year after year we could be riding on borrowed time. Not cheery I know, but maybe realistic. There is a reason the cup cars have a time out on them.

With regard to doing the replacement, though I have a shop doing them, probably not much more involved than doing the bearings.

dave-C2

I'm in the process of replacing all the wheel bearings on a GT3.

I appreciate the virtues of Krytox, but I'm hesitant to mess with the new wheel bearings and potentially degrade their life rather than enhance it. I have access to a tub of the stuff (which is nasty to work with).

The old rule probably applies here: if you have to ask, maybe you shouldn't be doing it...

How does one remove the dust shield without damaging it, replace all the factory grease with Kyrtox and reinstall the dust shield as good as new?

TIA for any help

FFaust

Thanks for asking Dave, I was wondering about the same thing

AudiOn19s

As a bit of a follow up months later down the road. My original plan was to pack the new bearings with NEO HP800. I took my uprights off of the car and to my dealer to have them remove and install the bearings for me. They had just gone through a very bad episode with trying to remove the dust seals, clean and re-pack the bearings on the Cayman race car they support so we decided against that route and put the bearing in as it came from the dealer...factory part.

One of the rears already gave out this season. IDK if it was switching to sticky tires for a couple of events, a bad bearing or what but in the process of the bearing destroying itself it also destroyed the hub.

...of course I catch this on Tuesday evening while going through the car for a track day this weekend New hub and bearing overnighted and are installed on the carrier, just picked them up time for a quick thrash tonight to put everything back together.