Greasing the wheel bearings

[pksjeep]

I just replaced the front wheel bearings on my 86 brat. What a pain. I got to looking at the front knuckle and thought about putting a grease zerk in it, I didn't at this time. Is there any reason that this should not be done? Bearing buddies have been used on trailers. The only problems I see are possibly weakening the front knuckle, and excessive grease being being flung around by the rotor and and axle.

[DaveT]

While that sounds like a good idea, the space between the bearings would have to be full of grease for the new to get into the bearings. The old dirty stuff would have to ooz out past the seals. Possibly even push them out. Brakes wouldn't work very well soon after that.

 

I put zerks on my trailer dust caps years ago, and after a few runs, found the inner bearing seals poped out due to the expansion from normal warming during use! Grease doen't compress like the air that would normally have been in there. I think the bearing buddies for trailers have springs to allow for the expansion.

[monstaru]

is that you patrick?

doin any 4 byin with that black jeep i saw?cheers, brian:grin:

[GeneralDisorder]

Bad idea. There's no drain for the old grease. The bearings should run with about 1/2 the cavity filled with grease. Soon you would have no air, and you would overheat and destroy the grease. The grease has to be able to expand and to "drop" into it's oil state to provide lubrication. This cannot happen if the cavity is filled.

 

Best thing to do would be to order sealed bearings. Just append a "-2RS" to the bearing number. I think the front wheels bearings are 6208's so you would want "6208-2RS-C3" (if that is indeed the correct number}. The standard open bearings are C3's so you want to make sure you get the same standard of tolerance. Order them through any bearing house. Cheaper than the parts store anyway usually.

 

GD

[4x4_Welder]

That's odd, at work we run greased bearings on the trailers, and I have yet to see a seal pop out. The hub caps get drilled and a zerk installed, they get grease every 10k at service time.

If you want a very good grease, though, try the Almagard from Lubrication Engineers. No signs of wear at 100k on those trailer wheel bearings, running about 16000 on each axle.

[XT6 Magic]

Every time I have an Axle/Hub out on my EA81 wagon I grease the bearings with a needle adapter and clean up the excess before reassembly. The original bearings have well over 200k on them and they are still good. Might not work for everyone, but... This technique also seems to work well for belt idlers as long as you are careful not to damage the seal on the bearing.

[idosubaru]

GD

ho, ho, GD Is back!

[Scoobywagon]

I've got an 88 wagon that I have done this to. Had to do wheel bearings and decided I don't want to have to do that again...ever. So, I put the knuckle in a vise on the drill press and drilled a hole in it opposite the brake caliper and tapped it. I packed the bearings with Mobile1 synthetic grease and installed them in the knuckle. Then, I pumped the knuckle full of grease until it started oozing out of the bearings. Cleaned up the excess and installed the seals.

 

If I were to do this mod again, I would probably mod up an axle stub so that I could install it in the bearings and use the drill press to spin it so as to mvoe the grease around and build up a little bit of heat while I add grease.

[GeneralDisorder]

You people just don't listen.

 

It's NOT the grease that provides the lubrication. It's the oil that is contained in the grease that does this. The grease gets hot, the oil drops out and the bearing is cooled and lubricated. If you pump the whole knuckle full of grease then it can't perform it's job. The grease just provides a lot of friction, the bearing gets hot, the grease fails, and then the bearing fails. A zerk fitting is a nice way to pump in grease but if you dont ALSO provide a method of removing the old grease (and presumably contamination, etc) then one would have to pull the axle to do the job anyway and thus the zerk provides no benefit.

 

The only good solution is to use sealed bearings, properly install the knuckle seals and bite the cost of replacement bearings every 200,000 miles (as if you would ever have to do a second set anyway )

 

GD

[Scoobywagon]

GD, I'm not arguing against you. Simply relating the facts. I HAVE modded the car in this way. It HAS worked up to this point. And I have transplanted those knuckles into another 88. Argue all you want, but the facts remain.

[GeneralDisorder]

GD, I'm not arguing against you. Simply relating the facts. I HAVE modded the car in this way. It HAS worked up to this point. And I have transplanted those knuckles into another 88. Argue all you want, but the facts remain.

 

Sounds just like all the morons that continue to pump grease into motors that ultimately have sealed or sheilded bearings because there's a grease zerk on the thing.... which is only there to shut people up after too many complaints to the manfuacturer about "how am I supposed to grease my bearings?" .

 

It WILL work - right up till it doesn't.

 

This is all pretty academic though as a properly installed bearing set should easily last the remaining life of the vehicle. You have to ask yourself - if I'm replaceing the original bearings at 150k..... how likely is it that somewhere north of 300k I'll still be driving this car? Unlikely at best and the drawbacks and potential damage that can result from over-greasing (by FAR the biggest cause of bearing failure) outweight the time and money it would take to replace them again in 10 years if the previous assumption is found to be in the affirmative.

 

Basically you are all wasting your time. Replace the bearings (-2RS sealed C3's), call it a day (or a decade in this case) and have a beer.

 

GD

[subuaroodude]

Just to clear things up:

http://www.engineersedge.com/lubrication/lubrication_knowledge_menu.shtml

As grease does not dissapate heat well packing a hub full can lead to overheating in some cases depending on components and loads, best to follow manuf guide lines.

[Log1call]

I have to agree with BD, too much grease is a bad thing.

 

It's well documented that bearings last better with the correct amount of grease in them.

 

In the case of wheel bearings, due to their heat and speed, they should be about half fill at most. A lot of modern front wheel drive cars have sealed bearings.

 

GD's logic is also correct... they last so long, you are more likely to cause wear by disturbing them, the seals are made to keep grease in.... Just live with the designers recommendations and your car will run economicaly for years. Modern cars with sealed bearings and ball joints out-last old car ball-joints and bearings by literely years.