Packing Wheel Bearings?

[rmayhew]

How often should you pack wheel bearings? I have the hub zirks that I shoot full every summer before travel. I figure I have put about 7,000 miles on the trailer total since new. I hear both sides, but I think packing every year is way over kill. What are your thoughts?

[Bill-N-Donna]

Last year I had the dealer check them when we had the Monty in the shop. They pulled one wheel and felt everything was ok. I haven’t done anything since but I would like to at least check them again soon. I do have a place for grease but I haven’t added any to it. I put too much grease on a set of bearings once (on a small S.O.B.) and it got into the brakes. I almost had an accident as a result of that. Too much is not a good thing.

[hookman]

I would not use the zerk fittings as that type of system the seal should be put in to stop the dirt from getting in and let excess grease out. With this type of installation the grease would go into the the brake drum area and the seal is put in to stop the grease from getting into this area so to much grease would blow out the seal.

[garyka]

I was told when putting grease into a zerk fitting on the axles you should only do one pump and no more than two or you can blow out the seals and end up with grease on the brakes.

[illapah]

I usually only use one pump and after towing for awhile so the grease and axle is warmed up to help prevent blowing out the seals. I don't think grease evaporates and constant care is probably worrying too much. I think that bearing wear is more apt to be happening than lack of lube.

[whiptail]

When we bought our Monty we were told to put in one put every year. We are not full timers. I am thinking of having the bearing checked next year.

[Art-n-Marge]

According to my manual for EZLube hubs that came with my trailer you grease about every 3000 to 4000 miles. But when putting in the grease you go real slow. This allows the grease to go into the bearings and the overflow to come back through the side you are putting the grease into. In other words, the grease goes into the fitting, through the bearings and cycles back out. If grease gets into the brakes that means the back seal is bad, has failed, or was blown out from too much pressure, or the outside seal is so clogged it won't allow grease to extrude. As soon as the grease is seen coming back out, then STOP. Wipe off the extruded grease real well and replace the rubber cap.

Illipah is right, grease does not evaporate. It loses consistency from heat (caused by rotating wheels, yes, even in cold temperatures). Greasing the hubs ensures that the grease is at its best consistency.

And if you keep them lubed regularly it should not take much. You can't necessarily go by one or two pumps because not all grease guns are the same. Go by what your hubs are telling you when the grease starts coming back at you while you slowly pump some in.

If you drive about 7000 miles per year, you might consider greasing the hubs every 6 months.

As for repacking, the EZlube maintenance is NOT without its flaws. Repacking is necessary to take out the bearings and actually check for wear, pitting, damage and stuff like that, that cannot be seen when you shoot in new grease. About every couple/three years, depending on usage, repacking (and possible replacement) can be done when you check the brakes.

Replacing bearings is another story. So are brakes.

Happy greasing,

[SlickWillie]

I was gonna C&P from the Dexter site, but apparently the page is not available. IIRC, Dexter recommends lifting the wheel and rotating as you slowly pump in grease. The design allows old grease to exit around the zerk. Personally, I wouldn't grease the hubs too often. Just my opinion, but I think it is overkill. How long did we drive our older model cars and trucks without servicing the front hubs? Same thing here, just on a straight axle. I would re-pack them when servicing the brakes. JMHO