Boxster S front wheel bearing replacement

[rastta]

I noticed my right front brake locking up under hard braking at Laguna last week. I think it's either a sticking piston in the caliper or a wheel bearing as it's accompanied by a metallic noise that isn't just pad noise.

The spare parts box that came with my car had a new front and rear bearing which are not the same size. In looking online it appears that some Boxsters have the same size bearing front and rear. The tool the Pelican has to remove them appears to work only on the rear bearing.

So I'm assuming that I would need a different tool for the front than the rear. Can someone confirm this and point me in the right direction? My local shop wants to charge me 4 hours to do the replacement and at that cost - and the fact that it appears that wheel bearings are a weak spot on these cars - i'm thinking of investing in the tool and doing it myself.

[steved0x]

If you have an S your bearings are bigger in the back. I have new bearings in my garage, I can micrometer them to tell the differences, but it is not major. The Sir B90-P can do front and back, and I bet the harbor freight FWD kit can do it too, and there is also a 944 bearing tool that may work.

I can measure my bearings but you can probably get the ID and OD from a parts website, those are the critical dimensions. Or if you have a hydraulic press, that is another option.

Fronts and back are very similar, with the main difference being that you have to remove the strut from the front carrier to get to the stub axle (I think, I'm still on the backs but am in progress right now to change all 4)

I mentioned on another thread that I had some more info, I'll post it tomorrow.

[rastta]

Originally Posted by steved0x

If you have an S your bearings are bigger in the back. I have new bearings in my garage, I can micrometer them to tell the differences, but it is not major. The Sir B90-P can do front and back, and I bet the harbor freight FWD kit can do it too, and there is also a 944 bearing tool that may work.

I can measure my bearings but you can probably get the ID and OD from a parts website, those are the critical dimensions. Or if you have a hydraulic press, that is another option.

Fronts and back are very similar, with the main difference being that you have to remove the strut from the front carrier to get to the stub axle (I think, I'm still on the backs but am in progress right now to change all 4)

I mentioned on another thread that I had some more info, I'll post it tomorrow.

I have a spare front and rear - so I can measure as well. Info on the SIR B90 is mixed - the Pelican version is definitely rear only and does just the rear and won't pull the hub and there are three versions - P1-P3. What i'm unclear on is whether the whole kit which is expensive will do the hub as well as the fronts. I've also seen that 944 kit - but again - it looks like it's for the rear only. If the regular boxster is the same front and rear - I would then assume the 944 tool would work - because it would work on the smaller of the two. NO wonder i'm confused!

[steved0x]

I added some more info to this thread with some more options. I haven't done the fronts yet, only the S Backs and the Sir tool worked great for those.

Wheel bearings are hard

I love the Sir tool for pulling the hub, much easier than using 3 long bolts and pressing it off like shown in the video I linked.

[steved0x]

If this is the Pelican one it can definitely pull the hub:

Hub/Bearing Extractor and Installer Porsche Kit PELTOLSIRB90P2 - SIR Tools - PEL-TOL-SIRB90-P2 | Pelican Parts

See this photo of me pulling my hub from the back.

[rastta]

Originally Posted by steved0x

If this is the Pelican one it can definitely pull the hub:

Yup - apparently the previous version didn't include the part to pull the hub - here's the text from the review of that part from their site and I just noticed it was from 2012:

This makes it easy, needs a hub extractor. Overall this tool works great for the bearing removal/installation and hub installation. I was amazed at how the tool pushed and pulled cleanly. For this, the SIR should get a 5, but.... The lack of a hub puller is a glaring ommision. The 911 has existed for almost 50 years. Why SIR tools can't figure out how to make a yoke/adapter that pushes on the face of the bearing retainer is beyond me. This is really the PITA task, and took several hours and ultimately a rented 5 lb. slide hammer and a 1-1/4" socket (as the hub driver) For this, I can't give SIR a 5. They (or someone with a good laser cutter) need to make a plate, that lets you push on the retainer.

So I take it that you have this kit and can do front and rear?

[steved0x]

I have the kit and have done the rear and am about to do the front.

Pelican shows it wrong on their website in Figure 16, when pulling the hub there is no backing plate used, just the big 27mm nut that is used to counterhold the back when you are turning the 24mm nut on the front side. I made that same mistake and twisted the end off my 3/8" breaker bar. Luckily the tool is much stronger than a harbor freight bar...

[rastta]

Originally Posted by steved0x

I have the kit and have done the rear and am about to do the front.

Pelican shows it wrong on their website in Figure 16, when pulling the hub there is no backing plate used, just the big 27mm nut that is used to counterhold the back when you are turning the 24mm nut on the front side. I made that same mistake and twisted the end off my 3/8" breaker bar. Luckily the tool is much stronger than a harbor freight bar...

Ok - I guess I should just order the Pelican kit - if it can do both size bearings. It's much cheaper than the master kit - which has a bunch of different size plates.

[steved0x]

Let me do the fronts first, I can start them tomorrow evening (wife's birthday today), I would hate for it to somehow not work on your fronts due to me saying it. I can also inventory the parts in the kit I have to see if it matches. It looks just like that photo though. Not the big master kit but the one on the pelican page here:

http://www.pelicanparts.com/More_Info/PELTOLSIRB90P2.htm?pn=PEL-TOL-SIRB90-P2&SVSVSI=936

[Topless]

Four hrs labor sounds real cheap to me. I have changed a lot of wheel bearings over the years and 986 are my least favorite. Just always a PITA even with the right tools.
If you MUST do this yourself, make sure you have all the tools you need including a puller and bigazz torque wrench with 6' helper to tighten your hub. Plan to spend 6 hours per wheel. You might get lucky and do it in 4hrs but "stuff happens". I cant wait to write the check to my local indy on this job.

Data point: In 10 years and 100+ track days I only changed 2 wheel bearings. One I did and one my indy did. My brother had to change all 4 on his car over the same period. One of his we did trackside at Auto Club Speedway Fontana, during a Time Trial event.

[rastta]

Originally Posted by Topless

Four hrs labor sounds real cheap to me. I have changed a lot of wheel bearings over the years and 986 are my least favorite. Just always a PITA even with the right tools.
If you MUST do this yourself, make sure you have all the tools you need including a puller and bigazz torque wrench with 6' helper to tighten your hub. Plan to spend 6 hours per wheel. You might get lucky and do it in 4hrs but "stuff happens". I cant wait to write the check to my local indy on this job.

Data point: In 10 years and 100+ track days I only changed 2 wheel bearings. One I did and one my indy did. My brother had to change all 4 on his car over the same period. One of his we did trackside at Auto Club Speedway Fontana, during a Time Trial event.

Like I needed to read this I know what you mean though. However - it seems like this is going to be something that isn't going to happen just once. I'm decent with a wrench and obviously wouldn't do it without the right tools. If I could drive the car to a shop it might change my mind....

[rastta]

Originally Posted by steved0x

Let me do the fronts first, I can start them tomorrow evening (wife's birthday today), I would hate for it to somehow not work on your fronts due to me saying it. I can also inventory the parts in the kit I have to see if it matches. It looks just like that photo though. Not the big master kit but the one on the pelican page here:

Hub/Bearing Extractor and Installer Porsche Kit PELTOLSIRB90P2 - SIR Tools - PEL-TOL-SIRB90-P2 | Pelican Parts

Thanks - I'm going to tackle taking the car apart on Friday to check the bearing and calipers.

[steved0x]

I got a start on it last night but stopped just short of starting to pull the bearing due to supper time.

For the fronts, I:

1. Remove the speed sensor wire
2. Removed the brake calipers and hung them using a S shaped caliper holder
3. Removed the rotor.
4. Removed 1 of my 5 studs (to clear the SIR tool puller later)
5. Removed the previously loosened axle nut.
6. Disconnected the tie rod end (pop - my first chance to use a ball joint tool)
7. Removed the sway bar link lower end
8. Removed the sway bar link upper end
9. REmoved the previously loosened axle nut
10. Slid the wheel carrier down the strut. I got stopped right before I was able to remove the stub axle. I need to slide the wheel carrier down a little more so the stub axle will clear the strut, but to do that I think I need to loosen the LCA inner end, and to do that I have to slide under the car and remove the front underbelly panels. Supper was ready so I didn't get to finish last night.

I think I can do the job with the front wheel carrier still on the car, just slid down enough so the stub axle can fit out the back. I'll find out tonight That would be good since I don't have a good vise to hold everything in, I need it on the car so the suspension can hold it in place.

Or... the KSports look like they may hang down less than the factory strut, so I may replace th strut first and button everything back up before doing the wheel bearing.

[rastta]

Originally Posted by steved0x

I got a start on it last night but stopped just short of starting to pull the bearing due to supper time.

For the fronts, I:

1. Remove the speed sensor wire
2. Removed the brake calipers and hung them using a S shaped caliper holder
3. Removed the rotor.
4. Removed 1 of my 5 studs (to clear the SIR tool puller later)
5. Removed the previously loosened axle nut.
6. Disconnected the tie rod end (pop - my first chance to use a ball joint tool)
7. Removed the sway bar link lower end
8. Removed the sway bar link upper end
9. REmoved the previously loosened axle nut
10. Slid the wheel carrier down the strut. I got stopped right before I was able to remove the stub axle. I need to slide the wheel carrier down a little more so the stub axle will clear the strut, but to do that I think I need to loosen the LCA inner end, and to do that I have to slide under the car and remove the front underbelly panels. Supper was ready so I didn't get to finish last night.

I think I can do the job with the front wheel carrier still on the car, just slid down enough so the stub axle can fit out the back. I'll find out tonight That would be good since I don't have a good vise to hold everything in, I need it on the car so the suspension can hold it in place.

Or... the KSports look like they may hang down less than the factory strut, so I may replace th strut first and button everything back up before doing the wheel bearing.

Did you test fit the tool to see if the plates fit the bearing? I'll be pulling the car apart this afternoon to do the brake calipers and check the bearing. Honestly - I'm hoping it's fine

[steved0x]

Originally Posted by rastta

Did you test fit the tool to see if the plates fit the bearing? I'll be pulling the car apart this afternoon to do the brake calipers and check the bearing. Honestly - I'm hoping it's fine

I will do that at lunch today, I didn't think to do that on a new bearing, and not just the old bearing in the car I'll post some photos.

[rastta]

Originally Posted by steved0x

I will do that at lunch today, I didn't think to do that on a new bearing, and not just the old bearing in the car I'll post some photos.

Well - it's not my front hub bearing. Just checked it - no play at all, spins with just the right amount of resistance, no noise or grittiness or roughness. Looking at the inner pad that I put in before the track day - the top 1.5 inches have no wear and the one it replaced had a lot of pad at the top and very little at the bottom. So it's got to be the caliper. Rebuild kit should be here today.

However, will still be good to know what tools are necessary in the event I may need to replace it at some time.

[steved0x]

Front bearing:
Pulling hub - good, same as backs
Pressing hub - good, same as backs
Pulling bearing - have to use the same plate as pressing the hub, fits the inner race, we'll see
Pressing bearing - press plate overhangs the bearing, but since it mounts flush to wheel carrier should be ok

Since base boxster uses the same bearing all 4 corners and it is the same as the S front bearing, it would suck if this tool is missing the smaller plate to make it work. I'll know this weekend.

Good luck on the caliper rebuild, are you going with high temp silicon dust boots?

[rastta]

Originally Posted by steved0x

Front bearing:
Pulling hub - good, same as backs
Pressing hub - good, same as backs
Pulling bearing - have to use the same plate as pressing the hub, fits the inner race, we'll see
Pressing bearing - press plate overhangs the bearing, but since it mounts flush to wheel carrier should be ok

Since base boxster uses the same bearing all 4 corners and it is the same as the S front bearing, it would suck if this tool is missing the smaller plate to make it work. I'll know this weekend.

Good luck on the caliper rebuild, are you going with high temp silicon dust boots?

Didn't got with the silicone boots - too much sensitivity to brake fluid. Went with the Centric kit which includes the inner seals. Caliper is apart now just waiting for the seals and boots to be delivered. I original bought the OEM boot kit from Pelican but it didn't have the inner seals. I might just keep it for spares as the boots don't last all that long. Easy to replace though.

[steved0x]

I've got the centric kit too, next time I have a break I am going to do them - one of my dust boots in the front is getting "funny" and I have to fiddle with it to get it to stay in the grooves.