Its been discussed blah blah blah. I was just curious when a good time to replace them is. My passanger side has started squeeling. It was alittle bit yesterday but today its really going. Am i able to regrease it and make it last longer or do i need to go ahead and replace it. I will look up the procedure in the search area when it comes time.

 

Ben

This is all my opinion as I have been the slave to many a bearing.

 

If going to the trouble of do a thorough re-greasing of bearings, I would just replace them while I am at it. With intact seals, you should not be loosing any grease.

 

I saved you the trouble of looking up the link:

http://www.ultimatesubaru.org/forum/showthread.php?t=77491

You are better off leaving it be till you can replace it. After a 10 year study of bearing life by a major corporation that had people who's job it was JUST to go around and zirk everything in sight they determined that:

 

1. 90% of all bearing failures were due to OVER-greasing.

 

2. Only a thin film of grease is required to get maximum bearing life.

 

3. Adding or regreasing bearings nearly always results in shorter bearing life than just leaving it be till it fails.

 

Baldor removed the grease zirks from their 50+ HP motors a few years ago, and I was told BY THEIR ENGINEERS that this was done because the tendancy was to over-grease the bearings and blow the shields out of them - having the zirk actually invites that tendancy. Alas the move generates so many calls to their tech center they put the zirks back in to stop the insane call volume .

 

GD

As a fellow, who had to grease many a bearing, automotive, or otherwise, what GD is saying is true, but does not apply to the wonderful world of vehicles.

 

The primary reason to grease a vehicle is water displacement, not lubrication, very little lube is required for long life bearing operation. It is the contamination of that bearing with water, and dirt, that kills it (in most cases).

It is pretty easy to pull the disc/hub assembly off and shoot some grease in there. Then push the hub back on. Repeat until grease is seen coming out around the inner part of the knuckle. It at least will quite them down till you can get a new set of bearings.

 

But then again, Get a good sized drift punch and replacing them is easy.

the few bearings i've had experience with were nearly devoid of "good grease", so i can't imagine that a proper regreasing wouldn't help (not overdoing it of course).

 

i've stuffed grease in CV's and they quiet substantially, i've regreased bearing and other assemblies before and they will run MUCH smoother and quieter as well. after 20 years the grease is all coagulated and not very "greasy" any more.

 

i'm not familiar enough with greasing wheel bearings, but i wouldn't be surprised if it helped. i don't know if adding a little in through the axle seal can get distributed enough or not through the actual bearing surfaces. i'd be willing to try it if i needed to though.

 

having a spare set of hubs to do the bearings on and then just installing the hubs is the only way i've done it, it's easy going and less pressure to get everything done at once.

 

i'm not familiar enough with greasing wheel bearings, but i wouldn't be surprised if it helped. i don't know if adding a little in through the axle seal can get distributed enough or not through the actual bearing surfaces. i'd be willing to try it if i needed to though.

 

If you use the hub to repeatedly squish the grease into the bearings, it works pretty good. If you unbolt the control arm bolt and swaybar mount, you can even pull the knuckle out off the axle stub a bit and feed grease in from the back side.

 

Also, at least the outer grease seal can be changed easily with the disc/hub assembly off. The axle has to be removed to replace the inner one.

I notice that the 6207 bearings that Subaru uses for our front wheel bearings come in double sealed format, pregreased with 2 built-in seals. Is there any advantage to using these sealed bearings vs. the standard unsealed ones? Will they last longer, shorter, about the same?

 

Also, the excellent photo write-up on replacing the bearings shows removal of the hub carrier. Is this necessary, or does it just make it easier? I mistrust all the corroded bits on my struts and carriers, I suspect that removal would be the hardest part of the job.

 

Thanks,

 

Rob.