Checking wheel bearings for potential failure?

[johns4104s]

How do you keep an eye on wheel bearings for potential failure. Heat, were do you check?  Noise, What type of sound?

Any input would be appreciated.

Thanks

John

[TomC]

Thee only real way to check wheel bearings is to take the wheels off and then pull the hubs off the bus to visually check the bearings. One of the things I first did before even taking my bus home was to have my mechanic pull all the hubs, convert all bearings to oil bearings, inspect the bearings (all were OK) and to have new oil seals installed. Also, you might consider having new wheel studs installed also.  Considering the age of the buses, this is good insurance.  Good Luck, TomC

[belfert]

What advantages do oiled bearings have?

The 1998 Dina I looked at Monday has oiled hubs and my 1995 has greased hubs.

[PP]

Aside from monitoring for heat, can you jack the wheel off the ground and check for end play?

[JohnEd]

I caught one once  when I felt heat coming from it during a stop.  I limped into a shop 20 miles down the road and he replaced the badly shreaded bearing.  He told me I was the only guy that ever had "that problem" that didn't come in on a hook.  He was forty something.  Point being....you gotta be lucky or be way ahead of the failure point.

I don't think that oil would be a better lube than quality grease.  Oil would be more reliable though and might be close to grease in lubricity.  What does oil lube conversion cost?  That is the deciding point, for me.  For our use, packing and adjust annually is sufficient.  Then again, with grease you face the recommended time interval of one year between packing and I am sure oil goes longer.  Maybe the decision is more complicated than I thought.

John

[bevans6]

What I do, not that it necessarily makes any difference, is whenever the wheels are off the ground I rotate them, feel and listen for roughness in turning, and for any end-float or play.  In most of my stuff, a lot smaller than the bus, that's the standard test and I do it out of habit.  My bearings are oil lubed at the front and oil lubed by the differential fluid at the rear.  that's fine for me.  Probably the best lube is a very light coating or fill of high quality grease, same as they use in sealed bearings, at least that's what my friend who sold bearings told me.  I like the oil in the front hubs, it's easy to check, you know immediately if a seal has failed from the fluid leakage, and they are dead easy to top up and check.

[JohnEd]

Oh yeah, I forgot!  I check my hub temps at EVERY stop and compare side to side and consider sun heating.  There is recorded of a bearing failure that didn't involve a temp spike

John