hot hubs

[5tonpuller]

I greased the wheel bearings this year and only have 1 driving me nuts. The left rear rear.
All the others just get warm ( all truck hubs do when there run ) but this one get really warm.
To the point where you can not hold you hand on it. Took it for a short ride and noticed the flange end getting really warm and the drum end still cool. regreased the out side bearing.
Time for a ride to see. Any ideas? Has to be something simple. Seals and gaskets are all new.
Snuged it up turning the wheel and backed off 1/4 turn. lined up the lock ( had to loosen the nut a smig ) and lock it down. Did the others the same way. Why this one? here some pics.

 

[doghead]

It sounds like time to replace that bearing.

 

[timntrucks]

yes bearing falure, but make sure you getting the oil up to the bearing too. must be some little rust or pitting that you cant see unless you really get a eye level look see with the old evil eye

 

[doghead]

The bearing is lubed by grease only,no oil.

 

[gringeltaube]

1/4 turn back is a lot! With all new bearings you should be able to almost feel some play. If not, something else is wrong! Bearing races not parallel, seats not clean or round, maybe a distorted hub? Loosen the nut a little further until you positively feel a little play. (Check at different positions of the hub!) Go for another ride, it shouldn't get warmer than the others. After readjusting, if the problem still occurs, inspect and measure the hub.
G.

 

[acetomatoco]

I would first adjust the brake on that wheel.

 

[gringeltaube]

I would first adjust the brake on that wheel.

Of course, and the only way to check for bearing play is with the brake shoes backed off.
But he said it wasn't heat from the brake drum but the (outer) axle flange end getting hot!?
5tonpuller let us know...!

 

[jwaller]

it looks to me like the bearing needs to be replaced alone with it's race. if you look very closely at the bearing and race pic you can see the bearing face is dull for about 85% of the length of the bearing and then the very end it's smooth and bright. it's should all be the same finish if it were wearing evenly. replace it and let that be the end of it.

 

[gringeltaube]

..... it's should all be the same finish if it were wearing evenly.

Are you sure? Isn't it the same case as the 2.5tons where the outer bearing is narrower and the rollers much shorter than the races width?
From looking at the pics, specially #4, I just can't find anything abnormal!

 

[Scrounger]

I don’t see any unusual wear on either the bearing or the race. The bearings only run on part of the race and the wear pattern looks normal to me. Since the drum isn’t getting hot that indicates that the brakes aren’t dragging. My guess with out looking at it first hand is that the bearing is just a little too tight. For the five to ten minutes that it will take to pull the axle and loosen the bearing, that is what I would do first. Just remember to check for bolt stretch and replace the lock washers on the axle flange while you have it apart.

 

[derby]

To the left of pic #4 in the center of the race is that a scuff or just the pic? I would clean the bearing and inspect for pitts,scuff marks and any cage damage.

 

[DaveP]

be sure to check the inner bearing races. these are often overlooked. just clean and dry the bearing real good and hold it just rite to the light and you can see right inside. also check to make sure the outer race is seated completly.

 

[Scrounger]

Did you find the problem?

 

[5tonpuller]

the book

I finely got time to sit and read. Here is what the book says. I did this to all 4.
I'm not sure if I got it to preload setting. Have to get a socket to fit the nut and my torque
wrench.
My $0.05 worth.
Matt

 

[Monty]

RE: the book

I've had bearings run hot when they were new, evan with the correct amount of load on them. The problems were that the bearings were over greased to the point that its restricting the rollers in the bearing cages during their rotation. Grease is good to much can cause some issues.
Chad

 

[benni72]

just my 2 cents worth, i've been in the bearing business all my life, born into it to be exact. start with the most obvious replace the cup and cone. if you still have a problem check to make sure axle isn't bent causing the bearings to bind. timkens really don't react to well to misalignment . also to much grease can be a problem as well. the way your setting the preload is fine, i usually tighten them up as much as i can and back off anywhere between 1/4 to a 1/2 inch. there is some side load, example when turning, but mostly radial loads put on these bearings and they really don't require to much precision to work correctly. heat can also be caused by the inner race spinning on the axle, you may want to use some permatex press fit assist to keep that from happening. also check where the seal rides, can be dragging and causing to much friction causing heat. hope this helps and just make sure as well everything is clean in the hub, no metal particles or dirt . again just my 2 cents worth, adam

 

[gringeltaube]

Did you find the problem?

 

[DaveP]

Not trying to hijack here but i have the same issue with the only set of wheel bearings that needed replacing on the M819. ran hot! just the outer. 212 degrees! in just 35 miles. backed the nut off 1/4 turn then locked it down and the temp dropped 40 degrees but its still hotter than the rest. i have been doing this kind of stuff for 30 years and never had an issue. I'm really scratching my hinny here on this one. new timkin bearings and races and the races were seated when installed. just run her again tonight up to the daughters Birthday party about 20 miles one way and temp went to 159. course it was at 70 mph but it shouldn't matter as the rest were at 112- 118. not trying to steal the thread just thought it was a like problem and why not squish them together. on a side note the inner bearing was pretty hard to get as everywhere i checked but one old buddy was on back order. i thought that was kinda strange also. if i remember rite its a 596A. going from memory here and that is not a good thing with the amount of sleep i don't get.

 

[OPCOM]

Do 5-tons have the same outer axle oil seal leaking isue as the M35?

 

[DaveP]

i dont know much about the 2 1/2 ton trucks but the 5 ton rears have an outer seal that keeps the gear lube from entering the wheel bearing. original had cork wedge and i used silicone.