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Old 03-08-2009, 10:36 PM   #1
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Default sti limited hubs on 02 wrx??

im looking to swap out my hubs. here is my question. will it bolt right up. will my sideshafts work with the hubs. if anybody has any info pls help with advice.

Ps i know ill have to buy new wheels

no worries guys got it sorted.

STi to 05 STi hub swap.


We are about half way though with the swap, I will have some one post pics soon. We should finish up tonight. Many thanks to Subaru of Gwinnett for parts and for helping to figure this out. Also have to thank Nasioc's Ver. III and for useful info. Mucho thanks to everyone at TopSpeed. Doug is loaning me some rear rotors and his wheels and tires (my only set of 05 wheel have victos on em) to get to the track this Monday, Will helped my incompetent ass with the tear down, and Jason for some trick bushings and staying late. Lastly, Tom Hoppe is the MAN!!!! <-- stayed up late to get most the swap down and is comin back for more wrenching and tomfoolery tonight. You rock buddie.
Down to business.....

Why swap: Wheel selection of 5x114.3 bolt pattern and SUPERIOR front hub and bearing.

For serious Auto-X'ers, DE, or club racers, there are only a couple production wheels wider than 8.5" for the 5x100 bolt pattern and custom will run $2k+. 5x114.3 has 'any' width wheel and many can be found in the cheap, light, and strong category.

The 05 bearing in the front is larger / stronger which will prolong life and resist knock-back longer. Plus the hub and bearing come as one sealed unit, which I call a unit hub, which bolts to the knuckle. Replacing a unit hub should take ~30 mins.

Will it work on WRXs/RS? Haven't reviewed all the changes but I think it will be just as easy. Edit: I understand that the axles are thinner, if the outer axle is also thinner then WRX/RS owners will need to swap axles....

What's different / what do you need.
2 - Unit hubs. ~$200
2 - 05 knuckles (subaru calls em housings) ~$200
8 - bolts to attach the unit hubs to the knuckle. These are not immediately obvious; usually when you are replacing the 05 unit hubs you would already have the bolts. ~$10 maybe
2 - 05 uprights. I had JICs going into this mod, so I just screwed on the new 05 uprights. If your not as lucky as I, you could buy take offs or upgrade... ~$depends, most coil over manufacturers will let the uprights go for $200-$300.
2 - rotors. Its hard to find take offs, but I did. I will upgrade to two-piece rotors very soon; these should reduce the heat transferred to the hub which I believe is the main contributor to flex and failure. Take offs $100-$200. New $350-$650. You might as well get two piece and keep your pimp new bearings happy.
2 - wheels. ~$350 and up for a pair

The rear is essentially the same design as 04, except the PRESS IN hub has a different bolt pattern. The rear on an 05 has a larger track which is only from slightly longer axles and links. The sub-frame is the same and the knuckle is the same part number. So you should only need:

2 - press in hubs. You will pull the 04 pressed knuckle and hub, bring it to your mechanic, to have them pull and rebuild with new bearings and the 05 hub instead of the 04. ~$200
2 - new bearing sets, pretty obvious from the above. might as well invest in some upgraded grease. ~$150 for the pair I think.
2 - rotors. New $220+
2 - wheels $350+

Some random info:

The rear axles and links for 04 to 05 are different lengths the 05's being slightly longer. This produces a looser but predictable rear end. autoXers may want this but buying spacers would be much cheaper...

Both the rear and front axles are different part numbers between 04 and 05. I believe that the rears are just a little longer. I know that the fronts have a different mechanical attachment to the tranny (04 can't go in 05 tranny and visa versa), they have different spline counts on the main axle bar (piece between the CVs), the spine count on the outside of the axle is the same (so 05 unit hubs will fit on 04 axles).

Some very experienced enthusiasts thought I would be fine just re-drilling my rear rotors. Aftermarket rotors range from 220 to 450 a pair for 1 pieces.

This conversion isn't for everyone; probably only makes sense for the autoX / road race crowd, however there are many. Like many conversions, planning / timing can be very important and save you money.

Knowing that the rear links were different lengths, I bought some adjustable lateral links (Poltec). however 04 rear links will work with 04 axles, your track will be ~1/2 inch narrower than an 05.

Even if you don't up grade links, this conversion would be a good time to upgrade some bushings, especially the rear trailing arm bushing, it is in the rear knuckle and is easy to remove with a press ONLY if the bearing has been separated and the dust/e-brake shield is removed. Else your must drill the old bushing out.

For a WRX or RS: I think axle/hub engagement is the big question. I believe that the bearing has been the same in the rear for some time... Someone on the board may know more. I have spare hubs at each end now though so if some one local has there axles.

5-29-05 Update:

Well we finished up late Friday. Big thanks to Subaru of gwinnett and the SE subaru warehouse for pressing the new rear hubs and bearings and rushing the 8 hub bolts over. Every thing went together fine. Except the front wheel speed sprocket on an 04 is in a different place than the 05 . I believe that the teath are the same but the 05 is closer to the end of teh axle. This means that with the center diff in auto, it sees infinite slip and locks the center diff and of course ABS is not happy. So for now, I pulled the ABS fuse and bump the center diff into manual every time I hop in. ABS and auto mode would be nice, and I have a few options to investigate to either get the sensor over the sprocket or press another sprocket on teh axle under the sensor, I should have answers on this in a couple weeks.

General 04 vs 05 info: thread

Buy my old stuff: here

gregr01: Depending on the brakes (heat), grip, and driving, the 04 bearings will last about 4 or 5 track hours before they start to flex very badly and fail. After 10 hard track hours they may be destroyed....

Update 5-03-05
I have had a few inqueries on the front hubs and knuckles. Once I get pics up they should be sold quickly. So If your doing a conversion, you shouldn't have trouble finding 04 STi owners that want a spare set of hubs to build up.

I had the rear rotors re-drilled for the new bolt pattern. I was a little worried but this should be a cheap and simple job for any decent machine shop. They slipped right on and the is no issue with balance.

So the only thing left to do is get a wheel speed gear made and pressed against the existing one. I will probably start this process (bring axle to shop, order gears, bore them out, etc) next week. Odds are I will have 10 or 20 gears made once mine are fitted and tested. Maybe a month till they're available.
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Last edited by SA2USA; 03-08-2009 at 10:43 PM. Reason: Found my answer on the third search.
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