F-Body wheel bearing installed

[-=Jeff=-]

I do know the ABS Module (Brain) is the same form 90-91..

EDIT..

totally different:
91-96:


90:

[WVZR-1]

Originally Posted by mike100

So does anybody know why they say you can't do the later parts on 90 and below C4's? I'm of the thought that there is a very specific reason or people wouldn't be listing them as for use on 91-up.

The WSS is different, the '90 has a WSS inserted through a bore in the spindle/knuckle that uses an air gap to the reluctor exactly like the rears on all C4's with ABS. I "know" that a minimum requirement would be a 2 1/4" diameter bore through the back-side of the knuckle/spindle to allow the accommodation of the hub/bearing for the later. I believe that for a '90 you just "pay-up" and get the right stuff.

There is likely one possible exception. If the WSS is frozen in the spindle/knuckle and can't be removed with out destroying it, it's already demolished then a person might consider the attempt both economical and a repair to keep the system functional.

I mentioned not being able to have both the earlier and the later side-by-side but I'm working on that. I'm not going to purchase something I don't need to satisfy my curiosity. Do I know it CAN'T? NO -- Might it? MAYBE.

Could the required 2 1/4" bore be done "on the car" using a metal cutting hole saw? It would eliminate the possibility of ruining the ball joint boots to remove the spindle/knuckle for a machining operation. No one's even considered it previously that I'm aware of. I mentioned earlier that I thought it maybe a valid thought for '84 - '85 owners that share the hub/bearing application but don't need the functionality.

This is a '90 and earlier spindle/knuckle and it would need a 2 1/4" bore in the back of the knuckle for starters:

http://www.ebay.com/itm/1988-1990-C4...-/121499953126

You can choose various images in that eBay to see how the WSS is done in the knuckle/spindle if you don't understand the differences.

[-=Jeff=-]

WV.. I added pictures to my reply to show differences..

I think you could use the 91 on a 90 with a harness mod to to the front as I know the ABS ECM is the same for both years

[WVZR-1]

Originally Posted by -=Jeff=-

WV.. I added pictures to my reply to show differences..

I think you could use the 91 on a 90 with a harness mod to to the front as I know the ABS ECM is the same for both years

Jeff - I knew and understood every bit of that. I questioned only the - is it actually economical, is the modification required to the knuckle/spindle a likely modification that can be accomplished easily and again economically. I believe maybe NOT.

This is a '91+ spindle/knuckle and you can see the minimum modification required (2 1/4") bore in earlier spindle/knuckle.

DSC_0078[1].jpg

[mike100]

! light bulb going off over my head- I get it now...totally different mechanical setup. I was quite sure the ABS functionality was the same. Never had a c4 older than this so had no idea.

[-=Jeff=-]

WV,

All is good, i have to wonder if you could (worst case) get a 91 Knuckle and swap everything, then you just need to connection for the newer wheel bearing.. Since the ABS ECM is the same, theoretically it should work.. but as you mention, the cost benefit may no longer be there

[WVZR-1]

Originally Posted by -=Jeff=-

WV,

All is good, i have to wonder if you could (worst case) get a 91 Knuckle and swap everything, then you just need to connection for the newer wheel bearing.. Since the ABS ECM is the same, theoretically it should work.. but as you mention, the cost benefit may no longer be there

That should likely do with just a change of the ABS connector or a quality cut/splice. My original interest in this possibility was actually for a fellow in "The Down Under" (AU) that has an '85 of course with no ABS and he needs to import what ever it is he buys. I thought/think if the F-body was available there(requiring a no ship) then the modification required to the spindle/knuckle would certainly be a more reasonable approach than the import of the correct stuff. The use for the '86 - '90 ABS was an after thought of that.

I'll gather the parts required to compare but at my leisure. I don't need and don't want to impose on a parts house to special order a hub/bearing just to look at. I've no idea why my snapshot ended up as it is but I see that it should work. What did I maybe do wrong?

Originally Posted by mike100

! light bulb going off over my head- I get it now...totally different mechanical setup. I was quite sure the ABS functionality was the same. Never had a c4 older than this so had no idea.

I maybe assumed that you hadn't had a hands-on of an earlier assembly and that's why I did the eBay link so you could see everything that's different and the snapshot of the '91+ I thought would confirm for you the difference.

[Billy Mild]

What is the best way to test wheel bearings? I think this might be one of my noises I hear on acceleration.

I shook the wheel both front and rear on the passenger side of the car and had a little play. I held the wheel at 12 and 6 positions. It moved a little bit.

Car has 70,000 miles. I would think wheel bearings would last longer than that, but who knows.

[Karl]

Lift the car and grab the wheel at opposite ends and look for play or a slight wobble back and fourth.

My car has 68,xxx miles.

[lbszr]

I've been running the F-body on my 90. ABS sensors removed. As mentioned, there would need to be a mod to the spindle for it to fit with the sensor on the bearing. I remove the sensor from the f-body bearing and have gotten the most life out of the bearings by filling the spindle cavity half up with 90 weight oil and giving the bearings a bath of oil. They seem to last significantly longer on the track with the oil, so the late model on the 90 has worked out good in this case.