sure wish there was some way to repack full of grease..

 

do both tires have to be up in the air at the same time or one side at a time. I've only had one side up at a time and they didnt wobble at all but i know sometimes both sides have to be up in the air for a true

 

one tire at a time will be fine. if you have any wobble when you try to rock tire back and forth when you grab the top, then you probably have a bad bearing. it could be ball joints too. when you rock it side to side, it could be your bearing, or steering slop. if you leave one tire on the ground, you can take steering slop mostly out of the equation.

The main reason that these go bad is the toe in being messed up. you need to definately have your alignment checked after you lift your truck. 94-00 I think had steering that would change your alignment whenever the ride height changed. This means when you put a heavy bumper, or winch, or lift springs, or springs start getting saggy, your alignment changed. this will absolutely kill unit type bearings, whereas old style bearings that were spaced further apart had more leverage to work against the tire.

If you keep going through hub bearings, your alignment should be suspected.

 

ok, i have no slop at all on either when only 1 is off the ground but a little slop when the whole front end is off the ground, must be the steering or u joints and not the bearings.

Sean

 

I really dont think that big nut has anything to do with bearing preload. I think those bearing units are all self contained so whatever preload there is its set from the manufacturer. The only thing that big nut does is hold the axle splined to the hub.

 

Thats what I always thought. I thought the nut just held the axle in?

Eric

 

yeah, the wheel bearing is pressed together, but the shaft and nut hold it together. take the nut off, and see how far you can drive with it off. about 500 feet before the wheel bearing comes apart. don't ask me how I know.

 

So it sounds like if anything the bearings arent cone style bearings so nut preload isnt really an issue. It just sounds like the nut holds things together.

 

You NEED to preload these unit-bearings... these are the same type of bearings on Jeep products (all the way back to 1984-ish) and Ford trucks...(after 97...) the bearing will want to seperate from the leverage that's on it from the tire and weight bearing down on the assembly from the engine, etc..

think of a tire on a rim, deflated, turning corners....with nothing to hold the tire to the rim, it will come off..

try this test (i suggest it only on bearings you are replacing...) take a three jaw puller, and attempt to pull the mounting flange off the hub, with out taking the 12-point bolts out of the back....you will be able to remove the mounting flange from the bearing...

you can imagine the lateral forces on the hub with that tall tire, big truck and heavy-a$$ engine...

even without a conical bearing, a flat bearing will seperate with lateral force, with nothing to physically hold it in place...that's why the axle nut is tighter than hell when removing it...

i've done MANY MANY MANY of these type of front ends. Chrysler took this front end design and utilized it when they consumed American Motors/Jeep. It worked well, and was cheap, and gave good ride quality. (Take a look at the front of a Cherokee, Grand cherokee, Comanche, newer wrangler 97+, etc..)

I've even wheeled one of these designs HARD with 33" tires on my porky 93 grand cherokee... the key to hub/bearing life IS the nut preload...

good luck guys!!

J