OK, so i go out of town for a relatives funeral and leave my 96 2500 4WD at home. While i was gone i get a call from my girlfriend saying she was driving home and it started grinding in the left front wheel/ hub area. This call was quickly followed by another call saying the wheel had totally locked up. What parts are usually destroyed in the front hub when these things lock up? I'm hoping for the best but have never had this problem before.

 

Sounds like a front wheel unit bearing to me! Pain to change out and often you lose a wheel when these go bad.

 

Hubs and all the fun stuff that more than likely has anything to do with your outer bearing assembly

 

OK, i was hoping it wasnt gonna be too bad but i haven't had a chance to tear into it yet. Do the axle shafts usually get damaged when the hub locks up? I already have the u-joints for it so those are no big deal.

 

Usually just the bearing gets destroyed.
Don't be tempted by the $125 Chinese unit bearings auto parts stores are selling lately.
They rarely last 10k miles and many have been reported broken right out of the box.
Expect to pay $175-$200 or more for a quality bearing.
Don't leave the dealer out of the bidding, often they come in with a good price.

 

is it possible to make these unit bearings greasable? i know they are sealed but with some work and changes is it possible?

 

Get the Timken brand replacement. Might as well do the brakes if it needs it while you have it apart. You can rebuild the calipers for around $10 bucks or exchange at parts store for new ones and some good pads. Just my .02

 

Yes they can be made greasable some guy did it over on the TDR , tapped a 90 degree grease nipple into it and drilled a 5/8 hole in the backing plate to get the grease gun in. I'll be doing it when the time comes.

 

My understanding has been if you grease a sealed bearing it will be overfilled causing the grease to churn, overheat and toast the bearing.
I'd like to hear what the long term success is greasing the sealed bearings.

 

Its possible , I think the guy was putting 10 pumps in a year or something. When I do mine I'll tap another hole on the bottom and put a plug in it so then I can flush the grease every 2-3 years . you'll have to take the berring out to do this but I usually have the front end apart every couple of years anyways fixing other issues U joints , axle seals etc..... Theres nothing like knowing theres fresh grease in there.