How much grease do you put in your hubs?

[DBreskin]

Re: How much grease do you put in your hubs?

repetatable

What word is that supposed to be? Respectable? Reputable? Repeatable?

 

[SuperNova]

Re: How much grease do you put in your hubs?

What word is that supposed to be? Respectable? Reputable? Repeatable?

Yes

 

[Captain Caveman]

Re: How much grease do you put in your hubs?

50% OF ALL FAILURES ARE DUE TO LUBRICATION ISSUES (contamination, inadequate
or excessive amounts, wrong lubricant)
30% OF ALL FAILURES ARE RELATED TO MOUNTING ISSUES SUCH AS TOO LOOSE OR
TOO TIGHT OF BEARING FITS
10% OF ALL FAILURES ARE RELATED TO STORAGE AND HANDLING PROBLEMS

So it seems that only a portion of the 50% are due to excessive amounts of grease. It would be helpful if there were a breakdown of the four categories, but my guess is that the other three lubrication causes (contamination, inadequate amount, wrong lubricant) are more prevalent than over-lubrication. Even if you score them equally, which I doubt, that would place the "excessive amount" incident rate at 12.5% of all failures...a far cry from 95%!

 

[bigdee]

Re: How much grease do you put in your hubs?

So it seems that only a portion of the 50% are due to excessive amounts of grease. It would be helpful if there were a breakdown of the four categories, but my guess is that the other three lubrication causes (contamination, inadequate amount, wrong lubricant) are more prevalent than over-lubrication. Even if you score them equally, which I doubt, that would place the "excessive amount" incident rate at 12.5% of all failures...a far cry from 95%!

I don't think anyone said 95%. This is just one factor that has to be considered when designing application that use tapered bearings. Wheel bearings are forgiving because of zero pre-load so chances are slim that over greasing will cause a problem.....BUT if that castle nut is wrenched down with the slightest pre-load and the hub and bearings are full of grease it WILL overheat and possibly seize. Simply stated there is right way and a wrong way. I have spent numerous times with bearing manufactures on application designs and issues.

 

[ricohman]

Re: How much grease do you put in your hubs?

I don't think anyone said 95%. This is just one factor that has to be considered when designing application that use tapered bearings. Wheel bearings are forgiving because of zero pre-load so chances are slim that over greasing will cause a problem.....BUT if that castle nut is wrenched down with the slightest pre-load and the hub and bearings are full of grease it WILL overheat and possibly seize. Simply stated there is right way and a wrong way. I have spent numerous times with bearing manufactures on application designs and issues.

Zero preload for tapered rollers? I have used preload on rollers for decades. I don't know of an application that does not call for preload.

 

[bigdee]

Re: How much grease do you put in your hubs?

Zero preload for tapered rollers? I have used preload on rollers for decades. I don't know of an application that does not call for preload.

We are talking simple wheel bearings.....they are not engineered to be preloaded.

 

[ricohman]

Re: How much grease do you put in your hubs?

What is a "simple wheel bearing"?
As a mechanic, I have never heard of that term.
Do you mean a unit hub?

 

[bigdee]

Re: How much grease do you put in your hubs?

What is a "simple wheel bearing"?
As a mechanic, I have never heard of that term.
Do you mean a unit hub?

Oh dear.....

 

[ricohman]

Re: How much grease do you put in your hubs?

Oh dear.....

I've serviced thousands of hubs in the past decades.
Never installed anything labeled "simple wheel bearing".
oh dear......

 

[ricohman]

Re: How much grease do you put in your hubs?

We are talking simple wheel bearings.....they are not engineered to be preloaded.

In my experience, a bearing that is to loose will ruin the spindle, the bearings and even loosen the race in the hub.
Torque them to spec, back them off until you have no play or a bit of play, then tighten your locknut. If you had a bit of play and now you have none, you have done well. If its still loose then you have to do it again. its a fine line that you work around. Its pretty much impossible to set a tapered set to zero so a bit of preload is the norm. If you can grab the hub and feel it move, you don't have enough.
Pinion bearings are set to about 12-15 inch pounds preload, for a used set. And these tapered bearings can last the life of the vehicle if set up corectly.

 

[scooper77515]

Re: How much grease do you put in your hubs?

Be nice guys...

This is from a local fishing forum I frequent. May or may not be "engineering" sound, but is definitely logical-sounding.

A

ssuming you have good seals meaning there's no grease all over the inside of your wheels, where exactly is all that grease you keep pumping into your bearing buddies going? Axle grease doesn't just disappear into thin air. Or does it?

Lets say you never pull your trailer at highway speeds long enough to warm the grease and centrifugally disperse it like it's designed to do. If that's you, your packed bearings will soon be running dry. Heat warms and therefore thins the grease. Once warm the centrifugal force of the hubs rotation disperses the grease outward towards your bearings. Otherwise your grease is staying in it's gel form therefore unable to thin out and properly lubricate your bearings. In a nut shell, No heat or enough centrifugal force .... no grease will be getting to your bearings. Next time you pull your hubs, the grease you packed in um last time will still be in its original form and likely its original color as well. And your bearings will be damn near if not completely dry.
Here's bearing buddies biggest failure. Bearing buddies were not designed to hold a liquid. (warm thinned grease) There is not a seal around the plate the spring in your b/buddy pushes against. Sure, when you pump fresh cool grease into the fitting the grease goes behind the plate and compresses the spring. The new gel form of grease will stay. (or at least most of it) Some of it will often ooze out the front. That ooze proves my point that b/buddies don't work properly. Once the grease gets warm and thins into more of a liquid state, instead of an ooze the thinned grease will start to run out the front of your b/buddy. That's where all the grease you keep pumping into your bearing buddies is going. It gets thrown out and disappears into thin air as you travel down the highway.
Secondly, none of the grease you pump into a bearing buddy will ever reach the inner bearing. The only way grease from a bearing buddy could possibly make its way to the inner bearing is if you have bad seals and the grease is being pushed all the way through the hub.

Here's a thought. .... If bearing buddies are so good, why aren't they used on automobiles? Properly packed and sealed automotive hubs can and will keep grease in them and last for 100,000 miles. Without constantly adding grease you'll never see a trailer hub with b/buddies do that. Not only do they let grease escape, every time you launch your boat they let water in.

Get rid of your bearing buddies and put regular caps on your hubs. (be sure to pack um full of grease allowing for the spindle and nut)

Lake Houston Fishing Forum, username Dragin Tha Line. Having a masters degree (NOT in engineering, even though I started there) has taught me to cite any quotations to prevent being nailed with plagiarism.

 

[maproy99]

Re: How much grease do you put in your hubs?

Well since I have hub caps on my trailer that cover the buddy bearing, wouldn't they get grease covered if the grease was coming out the buddy bearings? I just pack full, fill in the gaps and pump enough grease in my buddy bearing to add some pressure. The reason why you have to add a shot or 2 every so often to your buddy bearing is that the grease works into air pockets and the air escapes out the buddy bearing. So, add more grease or you will suck water in your hubs when you dip your trailer due to the contracting effect of cooling. Car hubs do not have to deal with getting submerged every couple of miles they drive.

Please feel free to post that back to the form where the guy posted that.

 

[scooper77515]

Re: How much grease do you put in your hubs?

OK, I am jumping in, now.

My hubs don't get hot. Not hot enough to cause enough expansion that dipping them in water will cool them down enough to suck water in.

Our water is 75-80 degrees, our air is about 90. The outside of my hubs are never warmer than the air temperature, and if so, only by a degree or 5. Dipping into water and having them quickly cool down 10-15 degrees? I doubt that is enough to cause the expanded grease to contract so much it suck water in past the seals.

Now, I agree that if my hubs were running hot, like very warm to the touch, to hot to the touch, dropping them in our water might suck in water. Especially if it was very cool water in the 60s, causing a 40-50 degree drop in temperature.

But that is not the case with my bearings. So far. Looking for wood to knock on....

 

[scooper77515]

Re: How much grease do you put in your hubs?

Several trips now. hubs full, caps empty, and no more lost caps, or leaky grease, or anything. Seems to be holding up well.

 

[Knot Waiting]

Re: How much grease do you put in your hubs?

I believe there is a rather famous quote favored by a rather famous member here that can be agreed on by both sides of this argument: "Ayuh, any grease is better than no grease at all"

 

[scooper77515]

Re: How much grease do you put in your hubs?

I agree. Any grease it better.

For an update. I have new hubs, new bearings, new caps, hubs are full of grease. No leak out from the inner seals, and the caps are still on tight. So I think the new hubs were the key to keeping them all together.

We have made 6 or 8 trips now, without incident.

 

[Vegas Naturist]

Re: How much grease do you put in your hubs?

Just my $.02 (not an engineer, but a heavy equipment mechanic for over 35 years).

Bearing buddies are okay, but they can give a false sense of security. I'm a firm believer in every year or so pulling the hub apart, and cleaning and inspecting the bearings/races, and replacing the seal. May be old school, but an ounce of prevention is worth a pound of cure.

John

 

[scooper77515]

Re: How much grease do you put in your hubs?

I do a full hub teardown, clean, and re-lube every season. Never had a bearing go bad on me yet.

But with the Buddies installed, I found some with a nice gray mixture of grease and water a couple of times...

Back to just good old fashioned caps and yearly lube, for me.

 

[skydiveD30571]

Re: How much grease do you put in your hubs?

In response to the heating debate on page 1:

For what its worth, I did an overhaul on my trailer a couple months ago. It has ez-lube axles. I took everything apart, cleaned, and repacked bearings by hand. We assembled everything but the cap and used the zerc fitting on the axle to push grease from the back to the front. Once basically full, we took the zerc fitting off, installed the buddy bearings, and gave them a few pumps making sure not to overdo it. I'd say my hubs are pretty full of grease.

After towing 30-45 minutes to the lake and stopping to prepare for the launch, I usually feel the bearing buddies by hand. It is a tandem axle trailer with drum brakes on the rear axle. The front axle is never very warm, justly slightly warmer than the air temp. The rear axle buddies are MUCH warmer, almost hot. I'm assuming the difference is the braking heat on the rear hubs. So I would agree that the heat from braking is much more significant than the heat from grease traveling in a rotating hub.

I plan on keeping an eye on them, and repacking by hand every year or two. Besides, the brakes need maintained anyways so why not take care of the bearings while I'm at it.

 

[jeffnick]

Re: How much grease do you put in your hubs?

Engineers know the rules...experts know the facts.
http://72land-n-sea.blogspot.com/2011/07/bearing-buddies.html?m=1