Front wheel bearing replacement AGAIN JPX 1996 Legacy

[JPX]

Last June, I wrote up this thread on a dry-run wheel bearing replacement that ultimately ended up being a real wheel bearing  replacement.  That was for the driver side front wheel bearing on a 1996 Legacy L sedan.

 

Well, on the same day that the car crossed over 200,000 miles on the odometer, it provided a new challenge.  

 

It started with an ABS light coming on along with some front end vibration at highway speeds.  This didn't seem like that big of a deal until the next morning when the passenger side wheel started to make horrible grinding noises.

 

I decided I should jack up the car and see what was going on.....I had already mentally prepared myself that a wheel bearing replacement was imminent.  Both front bearings had been done by a shop that I STILL regret taking it to.

 

The axle nut fell on the ground as I took the wheel cover off the car.   Further removal of the knuckle/hub assembly revealed what I already knew was the case......the bearing had been destroyed and the hub was simply banging around inside the knuckle housing.  It was so floppy that the brake rotor was grinding on the brake caliper bracket - rotor is toast.  The ABS light came on because the tolerance of the ABS tone ring on the hub was so out of whack from the sensor.

 

 

 

 

So off to the junkyard in the morning.

 

The first potential donor car did not have ABS - of course I only noticed that AFTER spending 20 minutes getting the rusted mess off the car.  Note in the photo below that the hub does not have the ABS tone ring.

The second car (shown below) was the correct match with the added bonus only rust belt operation can provide.  Unfortunately after pulling the CV out, I found that this wheel hub was totally destroyed.  I did manage to pick up a new-ish brake rotor since that needs replacing anyway.

The third car was an older 1994 Legacy wagon. This turned out to have a good knuckle/hub assembly and was the one that came home with me (after two hours of "practicing" removing wheel knuckles from 3 different cars at the junkyard).

 

 

The donor knuckle/hub assembly has a very different brake dust shield, but the parts are identical between the 94 and the 96. (back to 92 as demonstrated on the driver side bearing change).

 

I drove out the hub from the backside with a socket and a hammer - no slide hammer this time.   It cleaned up pretty nicely and I lightly polished the hub shaft.

 

And I used an air chisel to drive the outside inner race from the hub using the same technique as last time.

 

I have a new bearing, but I still need seals from the Subaru dealer.  The O'reily's and Carquests around here keep giving the wrong inner seal - the correct seal has a taller lip than they provide.

 

Next up, cleaning up the parts and pressing out the bearing race from the knuckle with the Harbor Freight puller kit #66829.

Edited February 27, 2013 by JPX

[JPX]

This photo shows the comparison of the 1994 hub assembly and the my 1996 assembly.  Only the dust shield is different.

[Fairtax4me]

Is that the bearing the shop replaced? The axle nut wasnt torqued properly. Looks like someone did the wail it on with the impact wrench method rather than getting out a torque wrench and actually torquing it to 137ft lbs. Also looks like it wasnt staked.

Anyway, the axle nut keeps the preload on the inner races of the bearing, if it gets loose the bearing goes kerplooey in no time. Just putting the weight of the car on the wheel before the axle nut is tightened is enough to damage the bearing.

Jam a big screwdriver in the brake rotor to keep it from spinning while tightening the axle nut. Then make sure it gets staked well to avoid backing out.

[jboymechanic]

I would say somebody owes you a refund.  I don't know how many "experts" on youtube I've watched replace wheel bears and pinion bears and NONE of them torque the axle or pinion nuts down to the proper torque.  Just hit it with the impact gun and call it good, that is why I will not take my car to anybody.

[JPX]

Is that the bearing the shop replaced? The axle nut wasnt torqued properly. Looks like someone did the wail it on with the impact wrench method rather than getting out a torque wrench and actually torquing it to 137ft lbs. Also looks like it wasnt staked.

Anyway, the axle nut keeps the preload on the inner races of the bearing, if it gets loose the bearing goes kerplooey in no time. Just putting the weight of the car on the wheel before the axle nut is tightened is enough to damage the bearing.

Jam a big screwdriver in the brake rotor to keep it from spinning while tightening the axle nut. Then make sure it gets staked well to avoid backing out.

 

Both front bearings had been replaced by a shop along with CVs several years ago......following that shop visit, I have refused to take my car to a shop.   The axle nut was staked reasonably well since I would glance at it as I had been in and out of each wheel for various brake and tie rod events.   In the end, the bearing was installed incorrectly which caused a failure leading up to it eating itself. 

 

I would say somebody owes you a refund.  I don't know how many "experts" on youtube I've watched replace wheel bears and pinion bears and NONE of them torque the axle or pinion nuts down to the proper torque.  Just hit it with the impact gun and call it good, that is why I will not take my car to anybody.

 

These bearing aren't the most reliable thing out there and the problem is aggravated by poor installation.   Since I haven't been able to find a shop with the SAME mechanics on duty to develop some trust with, I can feel confident that the work will be done right.

 

I ALWAYS carefully conduct torque setting operations - and for the axle nut in particular, due to the very large torque spec, I double check my numbers and tighten correctly.

Edited February 27, 2013 by JPX

[JPX]

Last night I worked on cleaning up some parts and getting out the old bearing from my newly adopted knuckle/hub assembly.

 

I had to use copious amounts of impact wrench on the Harbor Freight bearing tool kit to get the old bearing race out.  Lots of grease on the drive screw and the plates is critical to prevent overload conditions on the kit. Also, it helps to use a flat plate to START the bearing race press rather than going straight to the tube on the back of the knuckle.   This prevents damage to the lip of the bearing bore by the tube.  This means the plate has to be pulled out and the tube put back in to finally drive the outer race.

 

Remember that the snap ring must be removed before trying to press out the race - and that the bearing must be pressed out from the OUTSIDE to the INSIDE of the knuckle.

 

Once the bore was cleaned up, I could install the new bearing.  This was crazy easy and done only with the big hand wrench. 

 

Popped in the snap ring and moved on to installing the seals.  As before, the CarQuest inner seal STILL does not look right when compared to the higher lipped Subaru seal.   I used the Harbor Freight kit to easily press the inner and outer seals to the knuckle.  

 I had to bend and pry the dust shield off the old knuckle to clear the hub.  I bent it back into shape and bolted it to the "new" knuckle.  This has to be done BEFORE installing the hub or it will be a crazy mess trying to wedge the shield under the hub and around the bore housing on the knuckle.   The hub requires a socket or other small plate to support the inner bearing race properly - pressing the hub into the inner race without supporting the inner race will damage the bearing and shorten bearing lifetime.

 

At this point the knuckle and hub assembly were now back in working order.  What remained was changing out the damaged brake hardware.  When the bearing gave out, the hub tolerance was out so bad it caused the rotor to crash into the brake caliper bracket and grind.   I filed down the rough edges of the caliper bracket and installed the "new" rotor and pads.  

 

One little surprise that really slowed me down was that the ABS sensor bore was SMALLER on the 94 knuckle than on the 96.  When I measure the two ABS sensors, I found that the older sensor was indeed a smaller diameter.  I wasn't going to wallow out the hole, so I carefully sanded down the ABS sensor shaft until it fit.

 

I had to eye-ball the strut camber alignment - used center as the base point.

 

Then everything got torqued to spec (wheel in the air for the axle nut torque).   I took the car around the neighborhood to seat the brakes a little and then drove it around listening for any trouble.  

 

The alignment of the camber seemed to be a reasonably good guess as the car tracks straighter than before.   And if it is off, it is at least close enough to get me through the last leg of tread life on this set of tires.

 

Fortunately everything seems to be in order and the front end of the car is nice and quiet.    

 

To recap:

- Harbor Freight bearing kit has been used twice so far and is still usable (it would be nice to upgrade the threaded bolt, but it still works)

- grease the kit thoroughly when using it to prevent damage to the threads and making it easier to turn.

- START the press with flat plates to limit damage to the backside of the knuckle - then switch to the tube so the race can drop through.

- The 3 points above may not apply for extremely rusty cases where heat, penetrating oil and big hammers and ultimately a hydraulic press is needed.

- The kit really shines when INSTALLING bearings and is great for installing seals too

- 92-98 14 inch (non-Outback) hub/knuckle assemblies are interchangeable with same ABS-equipped 

----except for dust shields and potentially the ABS sensor bore.

Edited February 27, 2013 by JPX

[ivans imports]

check hub for wear where the iner berring rides on the hub if worn at all replace hub

[JPX]

check hub for wear where the iner berring rides on the hub if worn at all replace hub

 

I did check it on the "new" hub and the surface was in good condition. After all this trouble, the last thing I want is to put a new bearing on with a bad hub. 

[ivans imports]

good call on new hub we have a shop that has jiged up a lathe to weld them up and turn them back down when they get damaged we repair 6 at a time if that gives you a idea how ofter they go bad i have 12 rebuilt ones on the shelf