I'm destroying wheel bearings like they're going out of style.  You see I have this strange attraction to mud holes and water.  I offroad about once per month on average.  I need a new passenger side wheel bearing and I last replaced that one less than one year or 6k miles ago. 
    I have replaced my auto locking hubs a few years ago with manual ones from a tracker (if that makes any difference) and the gaskets where the locking hub mates to the hub body are long gone.  I have been using gasket maker stuff from advance or autozone.  Could that be my problem or is it simply the fact that last time I went offroad my hubs did too much scuba diving in muddy, sandy water? 

Any tips for sealing hubs better?  Any special grease I should use?

Thanks

Jon

Form a gasket should work very well for sealing the hub mating surfaces.  Hubs can still generate moisture inside the assembly from condensation.  When your hubs are locked, they generate heat from the friction of the hubs engaging the splines of the CV shaft.  When you have been driving a while and then submerge your front axles into the water you cool the hubs quickly and cause condensation to form.  If you run your truck in the water often, you should consider periodically pulling, cleaning and lightly lubing the hub internals.  The same happens with your diffs.

Did you replace the inner axle seals at the same time you changed your hub bearings or hub assembly?  If not, it may be the inner bearing seal is allowing moisture and extra dirt through to the bearing surfaces.  The inner knuckle seals are design very well, but if they are worn, they aren't very efficient at keeping water out and if they are really worn, mud and sand can be pressed into and past the seal surface as well.  The other question that comes to mind is:  are you properly torquing your hub bearings down when you replace your hub/wheel bearings?

Sand and mud are brutal on seals.  Even if you wash/spray your truck down after off-roading, it is very difficult to fully remove sand particles and mud from up against the seals.  Especially on the front axles. 

Did you replace the inner axle seals at the same time you changed your hub bearings or hub assembly?  If not, it may be the inner bearing seal is allowing moisture and extra dirt through to the bearing surfaces.  The inner knuckle seals are design very well, but if they are worn, they aren't very efficient at keeping water out and if they are really worn, mud and sand can be pressed into and past the seal surface as well.  The other question that comes to mind is:  are you properly torquing your hub bearings down when you replace your hub/wheel bearings?

Sand and mud are brutal on seals.  Even if you wash/spray your truck down after off-roading, it is very difficult to fully remove sand particles and mud from up against the seals.  Especially on the front axles.

Great advice. Replace all the inner seals. 

I have a couple thoughts.  Is your suspension lifted or modified?  When you lift/modify your suspension, you need to correct the wheel chamber/angle.  If not, your tires look "pigeon toed" and it does three things:  odd handling, very premature tire wear, and it is rough on bearings and suspension parts.  Second---and most important, are you changing your bearing races when you change the bearings?  I too was wearing out bearings at an alarming rate on my sidekick.  I was replacing the seals, fresh grease, torquing to spec but I did not have races put in because I was lazy, cheap, thought they were ok, and I did not have a press.  After changing the driver once and the passenger twice in a year, I bought Timken bearings and races and took the hubs to Muffler man.  He charged me $25 to press in the two new races and gave me back the old ones.  It was immediately noticeable, the races were severely worn, pitted, and scored.  I have not had a problem since, But I clean and lube the manual hubs and clean & repack the wheel bearings every two years.

Torque the bearings to FSM specs.  These are not the old style bearings that you tighten with a pair of channel locks, the requirement of 150# is there for a reason.
Break down and buy the wheel bearing socket ($60 online), it is hard to make one that will go to 150 psi.

Second---and most important, are you changing your bearing races when you change the bearings?  I too was wearing out bearings at an alarming rate on my sidekick.  I was replacing the seals, fresh grease, torquing to spec but I did not have races put in because I was lazy, cheap, thought they were ok, and I did not have a press.  After changing the driver once and the passenger twice in a year, I bought Timken bearings and races and took the hubs to Muffler man.  He charged me $25 to press in the two new races and gave me back the old ones.  It was immediately noticeable, the races were severely worn, pitted, and scored.  I have not had a problem since, But I clean and lube the manual hubs and clean & repack the wheel bearings every two years.

What exactly are you describing as the bearing "races"?

If we look at a typical bearing, it will have an inner race, an outer race, and a number of rolling "elements" either  balls or rollers, usually held in a pressed sheet metal cage that locates & separates them...



This first image shows a ball bearing with the outer race has been cut away so that the balls and the cage are clearly visible - this type of bearing cannot usually be disassembled without destroying it.

With roller bearings, especially taper roller bearings, the inner race and the rollers are not captive...



This second image shows a typical taper roller bearing, with the outer race removed so that the rollers & cage are visible.

The reason why I'm asking this question is that for me, and I believe for most of us, the races are an integral part of the bearing and to not replace the races would be like replacing only half the bearing - if the rolling elements are worn, the chances of the races not being worn is slim to non-existent.