Repacking Axle Wheel Bearings with; GREASE??!!

[Greenleaf]

I read with interest in the most recent TDR Magazine that it is recommended to repack the rear axle wheel bearings with grease? Is this the writers opinion?



My Timken bearing Recommended Practice #618 gives the clear warning to NEVER pack bearings w/grease which operate in an oil bath. The grease, said Timken, restrics the flow of oil into the bearings and damage "may" result.



I have followed the Timken RP # 618 all my years as they make the bearings, so I feal more comfortable doing so. Besides, if you don't follow the directions and someone gets hurt, I have documentation that I used the manufacturer recommended practice. Very important when you wrench on a school bus.



Do many folks follow a different practice?



Is this something that a garage will do to cut corners when working on a customers vehicle? I understand time is money and may eliminate jacking up the truck to drain oil into the bearings.

 

[GHarman]

Greenleaf, I am not a professional wrench. However I did listen to some good advise on TDR, that it is unnecessary to grease oil bath bearings. I think that came from PToombs! Thanks Pete! While working on the rear axle of New Ugly, last summer. My friend and I had the axles out and drums removed. We replaced seals and did the brakes, pulled the pod cover and inspected the guts and replaced the axle oil. The bearings were in good shape. So, we cleaned the bearings, blew them out and soaked them in new gear oil. I dont believe time was any consideration but they worked just fine, even with the pod oil installed a couple of days after the hubs were buttoned up. Had to wait for the RTV gaskets to setup and other delays. It seems that the oil is more than adequate. However, It did not enter into my mind that the grease could become a barrier to proper lubrication. I thought it would wash out, over time. Thanks for this information! Greg

 

[GCroyle]

Additional Do Not.

Greenleaf,



Since you have a copy of the Timken RP, can you check for our benefit, I remember somewhere that the practice of drying a freshly cleaned taper bearing by the use of a shop air gun and making a turbine out of it is a strict NO NO!



I remember seeing a Timken field failure book MANY years ago and it was chock full of this caused that explanations, really good stuff. Many related to seemingly un-related causes, accidentally grounding through a bearing for welding, comes to mind on equipment. Installation caused failures etc.

 

[Greenleaf]

That isn't in the Timken RP. You may be thinking of the "Tech Tips", "Tapered Roller Damage Analysis" Volume 2. But, in fact, there is a warning to never spin on all the tech tips issues.



In college, the shop instructor said he witnessed one fellow spin a tapered roller to the point of exploding. The cage came off and spun up along his wrist. That would be like a knife.

 

[rscurtis]

Years ago, I worked on a '63 International 4X4 HD pickup. The rear hubs were dry, ie, were packed with grease. The outside bearing retaining nut had a face seal on it to keep axle oil from running into the bearings. It's the only one I'd ever seen like that.

 

[BDaugherty]

I've heard stories of new rear wheel bearings burning up before lubrication got to them. I don't grease mine, but I have this little procedure that makes me feel better:

1. Install new wheel bearings and put everything back together.

2. Fill differential with your choice of oil.

3. Jack up one side and then the other so that oil runs down the axle tube and fills the hub.

4. Top off the differential.



If I was going to use some grease on the bearings, It would be an assembly grease such as this one:

Lubriplate Online Store - Detail

It's made to lubricate a part until it gets oil. Then it dissolves.

 

[PToombs]

If I clean and dry the bearings I put a very thin film of grease on the race only and assemble it. Then I fill the diff a little over so it's running out of the hole. Never lost a bearing yet, and I don't jack up either side to move the oil.



Spinning a bearing with air is a big NO NO! I can see it exploding all over every time I have to blow one out. I'm careful about blowing them out.



I have seen grease bearings like rscurtis described. It was on an older, I think 70's, pickup.



You're welcome Greg!

 

[SRadke]

I did the brakes on the back of an 02 Ram. Put it all back together as spec, dry and sent the man on his way. He made it ~20 miles, flat ground, no corners and one bearing came apart. Hub cocked up, brake now dragging, he kept going, things got hot, he stopped, didn't see the problem, got back in thew it in 1st and twisted the axle off.

Ended up twisting the end off the spindle/axle tube as well.

Moral of the story... . put enough grease on them they'll hold up till the lube get's there, or tip it up and force it there. I learned the hard way.

-Scott

 

[CumminsPower98]

1. I install the hub, pump it full of oil to the point it starts to run over the outer race, install outer bearing and button it up.

2. Top off the diff. jack up each side or park on hill both ways.

3. Top off diff.



I have done this on many vehicles and never had a failure. To each his own. I like the idea of using assembly grease (BDaugherty) if a grease is going to be used.