Wheel Bearing Temps High, grease & Preload Q's

[BugEyeBear]

What is the acceptable operating temp for a wheel bearing?

What temp is too hot?

I just had the rear wheel seals on the passenger side replaced and now they are running 130 degrees after a short 10 minute drive on the freeway, 180 degrees after a 20 minute freeway drive. The driver's side (untouched by the repair shop) are running constant at 80 degrees.

Is 180 degrees too hot? What is normal?

I need to get this fixed prior to doing a 400mile drive in a couple of days, so any help would be GREATLY appreciated

-Bear-

 

[BugEyeBear]

Wheel Bearing Preload Torque

What is the correct Rear Wheel Bearing Preload Torque & Final Torque?

& what is the correct procedure?

I've seen some posts on front wheels that say preload to 50 ft lb while rotating wheel, then back off 1/4 turn, & then install jamb nut to 100-150ft-lbs.
Is this correct?
Is this the same for the rear bearings?

What is the Tech Manual reference number for this procedure?
(I'm looking.... But if you already know....)

I need to get this fixed in the next couple of days, prior to a 400 mile road trip, so any help would be greatly appreciated!

-Bear-

 

[dburt]

Old rule of thumb- if you can't hold your hand on the bearing cap due to the heat, it is most likely too hot. Could you have a brake shoe dragging that is causing the heat build up from the drum to transfer to the bearing caps? Just something to check.

 

[BugEyeBear]

Wheel Bearing Grease

What is the correct or preferred wheel bearing grease for the Deuce?

My mechanic said that the grease that was in there at disassembly was clear. Looked like general purpose grease.

He put in Red Synthetic Heavy Duty Moly Grease when he replaced the seals.

Now my bearings are running hot.
I can't imagine that this is due to the grease, but I'm trying to cover all of the bases...

(I suspect improper bearing preload or defective bearings, but I'm trying to cover all of the bases...)

I need to get this fixed in the next couple of days, prior to a 400 mile road trip, so any help would be greatly appreciated!

-Bear-

 

[BugEyeBear]

Brake is not dragging. Already checked that. Wheel spins freely when jacked up off the ground.

But you DEFINITELY CAN't hold your hand to the cap for more than a few seconds before it gets too hot! 180 degrees! "OUCH!"

(I'm suspecting incorrect bearing preload, or bad bearings, or maybe even wrong grease...)

Anyone know what the TM is for rear bearing install/preload?

-Bear-

 

[wsucougarx]

Was you outer wheel seal made in China? Apparently there is a design problem with them. The actual rubberized outter edge comes in too close of contact with the outter wheel bearing causing it to drag---thus causing heat. There is a thread in here somewhere where a guy took the seal and tweaked it with a press. Now he only tweaked with very minimally, so much so his measurements were with a micrometer. Seems the middle part of the outer seal unit (part that the axle nut comes in contact with) needs to be pushed inward. This helps to relieve the pressure on the bearing. I hope this all made sense.

 

[wsucougarx]

Found it!!!!!

http://www.steelsoldiers.com/deuce/31749-hot-hub.html

 

[wsucougarx]

If I remember correctly. I was told to stay away from Moly Fortified greases b/c of the bearings. Something about the type of bearing we have....hopefully someone can chime in. I use Chevron Delo EP Grease (blue color)

 

[gimpyrobb]

Good call Mike, I don't know how I missed that thread, but I did.

 

[doghead]

I merged your three threads into this one.

When dealing with one problem, it is better to ask all you questions in one thread, than 3 separate threads. Since all three threads were getting the same answers and dealing with the same problem.

 

[clinto]

Pertinent info:

https://www.steelsoldiers.com/showthread.php?3202-axle-leak.html

 

[Lex_Ordo]

For grease I use Kendall Blue high temperature lithium grease. It is blue, and is a good long lasting grease. I have it on my winch, all my lube points and in one axle that has had the two wheels bearings repacked.

 

[BugEyeBear]

I merged your three threads into this one.

When dealing with one problem, it is better to ask all you questions in one thread, than 3 separate threads. Since all three threads were getting the same answers and dealing with the same problem.

I respectfully disagree.

While the 3 threads are indeed related to the same issue that I'm currently experiencing, I OBVIOUSLY felt that the 3 topics were distinct enough to warrant 3 distinct threads.

Now with the 3 threads combined into 1 the responses are somewhat confusing, and the thread titles on "Bearing Preload Torque" & "Bearing Grease" are not visible on the main Deuce list of threads.

Don't get me wrong here, I can understand your position as a moderator to keep the number of threads to a minimum, and combine threads where you see appropriate.
But now someone with speciific experience in wheel bearing preload torque or in wheel bearing grease is going to have to ALSO have an interest in the "Wheel Bearing Temps" topic before they will find my other questions.

This Forum is a great resource!
BUT it is often difficult to find a specific answer because it is frequently buried deep within a thread that wanders amongst several related topics instead of sticking to one.
I was trying to avoid this issue by keeping each of my 3 posts focused on one distinct topic.

So much for that attempt.....

 

[doghead]

oops, sorry! I just changed the title to list the other topics.

I think the cause of your heat is your seals. Others have seen this before, the dish may be putting too much pressure on the face of the seal, causing the heat.

 

[BugEyeBear]

oops, sorry!

I think the cause of your heat is your seals. Others have seen this before, the dish may be putting too much pressure on the face of the seal, causing the heat.

So is there a preferred place to get the "correct" seals that don't cause this problem? OR is modifying the seal the only solution?

BTW: The new seals that were just installed came from Memphis.

I've read the threads that discuss the seals causing heat builld up.
& I don't 100% understand just what causes the heat.
Is it friction between the seal & some other part? IF SO, exactly where does this contact occur?
Would this actually be enough to cause the 100 Degree temp difference (between the untouched driver's side rear wheels to the newly replaced seals on the passenger's side rear wheels) that I'm experiencing?

I've gotta admit, I'm a bit sceptical that this 100 degree difference is caused by a seal rubbing. But then again I'm open to any suggestion that helps to resolve the issue!!
(Right now my thoughts tend to lean more towards incorrect bearing preload or incorrect bearing grease...)

The Mechanics that are working on it have had it apart 2x now already, and they are about to tear it apart for time # 3. I doubt that they will want to even attempt a 4th time, so I'm trying to provide them with as much supporting info as possible.

(Note: I would normally tackle this repair myself, but currently I am 400+ miles away from home..... & I'm stuck here until this is fixed well enough to safely make the 400+ mile journey back to SE Georgia. Now going into day #5 of this predicamant, so I apologise if I'm coming across as being a bit uptight. I didn't get much sleep last night as I was searching forums & the web for an answer...)

-Bear-

 

[doghead]

I can believe that too much preload could be a factor. I don't think that grease type, will ever make that much temp difference. I have not experienced the high hub heat from new seals personally. What I understand from what I read here is that some people have had the same problem as you, and the "bent, hammered, flattened") the metal center disc of the seal, to slightly decrease the installed pressure of the seal lip(face).

fwiw, I think I remember that my hubs measured about 105-110F on a 70F day, after driving for a while.

also, I once had a hub that was hotter than the rest, after some inspection, I actually found that the brakes were installed incorrectly. I was using an ir gun, and I really didn't see the heat in the drum!

 

[Armada]

I just went through this fixing a leaking rear hub. I dismantled, cleaned, put in all new seals, cork, (bearings were ok), used the red grease, and tightened things up. I left just a tiny bit of play in the bearing then tightened the outer spindle nut down and 'locked' it. Drove the truck 15 miles and the hub was excessively hotter than the rest. Not 180 degrees hot, but too hot or too warm in my opinion, compared to the others. I raised the wheels back up and checked again for 'play'. There was none. When tightening the outer spindle nut down, it took out what little 'play' that was there for some reason. I loosened the inner nut just a little more, tightened up the outer not and locked it, and made sure there was still some play. Finished putting back together and drove it, and all is fine. You might want to try it, may help your situation.

 

[O.D. Fever]

I agree with the seal could be the problem, also the preload on a new bearing should be looser than a used bearing. Type of grease could also be an issue if it is too thick and if there is too much grease that will cause a heating problem. all of these things can effect the temp. Can drive a guy crazy. Good luck..Joe

 

[BugEyeBear]

THANKS for inputs!!

THANKS Guys for all of your answers & suggestions!

The repair shop has disassembled the rear wheel bearing assys again...
They are inspecting the bearings & races, and will be packing them with a non-Moly high temp grease prior to reinstall.

For your reference here's a data sheet that I found on the MIL-G-10924 Grease that is refererred to in the Lubrication Order.
GREASE, AUTOMOTIVE AND ARTILLERY GREASE
Appears to be a Lithium 12%, Polyalphaolefin (a polymer) 63%, Distillates 12% composition, with a boiling point of 700 degrees F, & a melting point of -70 degrees F.
So I would think that a High Temp Lithium Grease with similar properties should be a suitable replacement.

The repair shop is also going to modify their bearing preload procedure to include the 1/8 turn nut back off, as noted in the TM.
Here's the procedure they are now following:
1. Torque the inner adjusting nut to 150 ft-lbs while rotating the wheel at least 2 revolutions.
2. Relieve pre-load by backing off the adjusting nut 1/2 to 1 full turn.
3. Re-torque the inner adjusting nut to 50 ft-lbs.
4. Then back off nut 1/8 turn.
5. Install adjusting nut star washer, and outer adjusting nut .
6. Tighten outer nut 100-150 ft-lbs.
7. Bend over tangs of the star washer to secure the adjustment.

They are also planning on taking a close look at the outer seals to see if they are dragging on the race.
I'm not sure if they will attempt to modify these seals (mod noted in other threads), so IF the seal is dragging this might be something I'll just have to live with untill I can mod them myself.


I'm keeping my fingers crossed that THIS attempt will be successful!

I'll let you know what the outcome is....

-Bear-

 

[O.D. Fever]

Best of luck, fingers crossed.