Wheel Bearings

[dmad1]

Are trailer wheel bearings made of such low quality that they will only last a year or so? I don't understand why they need so much maintenance compared to autos and why it is suggested you carry a spare set or two. Most autos I have owned in my 60 years of driving have rarely needed new bearings. And most were never greased. The last boat I had, I kept for 17 years and it never needed new bearings. Granted, I did grease them every once in a while because they were submerged. Over the years we have had lots of different types of campers and have never had bearing issues. Just wondering...

[Gompka]

Originally Posted by dmad1

Are trailer wheel bearings made of such low quality that they will only last a year or so? I don't understand why they need so much maintenance compared to autos and why it is suggested you carry a spare set or two. Most autos I have owned in my 60 years of driving have rarely needed new bearings. And most were never greased. The last boat I had, I kept for 17 years and it never needed new bearings. Granted, I did grease them every once in a while because they were submerged. Over the years we have had lots of different types of campers and have never had bearing issues. Just wondering...

I think the people carrying spare bearings are just being super prepared. Most napa auto stores and other auto stores carry the bearings. These type of wheel bearings and most in the rv industry, except for the newest 2018+ models like (Airstream), require you to grease the bearings. You used to have to grease bearings in cars as well before the wide adoption of sealed axles. All the maintenance that the axles should need is added grease and repacking the bearings every once in a while, i do mine at about 20k miles.

[Jack L]

There are a lot of import bearings that are poor quality, and sometimes, the RV industry wants the lowest price component so that is what you wind up with. Also, smaller wheels and tires turn many more revolutions than the tow vehicle.

[redbarron55]

The trailers that I have had problems with have all been boat trailers.
This was before the advent of the bearing buddies etc.
I got the EZ lube hubs with the new Flexiride axle I installed on my rebuild and they ran a little warm until the excess grease worked its way out.
My guess is that if I were to relube according to the instructions they would run warm again with the churning of the excess grease.
I did give them a couple of shots of grease before we started out 9200+ mile trip two months ago.
Ran cool (cooler than the tires by the way).
I always check them every time we stop. (back of fingers on the tires and hubs)
I think over greasing could cause trouble as well especially with hubs that do not have a way to expel the excess.
A bearing should never be packed more than about 1/3 full and even than will be pushed out of the races, anyway.
The lubrication actually comes from the oil that migrates from the grease into the race anyway.
Only very low speed bearings can keep any grease in the races and too much grease churns and can overhead cooking the soap drying out the oil and starving to bearing of oil.

[Doug Arthurs]

I haven't really seen any problems from Boat or RV bearings. I find the new sealed auto wheel bearings more problematic. I do have bearing buddies on my boat and add a little before each long trip. My Boler trailer I repacked when I first got it just to make sure bearings were in good shape. My Bigfoot I did the same this summer after I bought it. Pull everything apart clean and repack. Probably won't look at it again for a couple years.

[Daniel A.]

If the wheels are not running hot there is no real need to pull them apart.
When traveling I check the temperature at rest stops and would only pull the bearing if running hot. I do repack them early in the year.

[Bruce H]

Bigfoot's oem bearings are marked "made in china". Replacements from Autozone, Pepboys, etc. are mostly marked made in Romania. A couple of different times I have had auto parts stores order Timkin bearings for me (over their objections). Timkins are made in France but they are excellent quality. The best thing to do is just order them from the internet. You won't find them in an auto parts store. I just completed a 4,200 mile western tour this summer. In the middle of it I had a hub getting hot so I did a parking lot bearing replacement. While digging through my bearing box (a metal army ammo can) I found some Timkins marked "made in USA". I could not see anything wrong with the chinese bearings that were in there and I know the castle nut was not too tight. They still had plenty of grease on them. I replaced them anyway.



The hub still continues to run a little warm with the new bearings, not hot, just a little warmer than the others. The only other things that could cause that are a brake dragging a little bit or the wheel is a little out of alignment causing side pressure on the bearings. There is no adjustment, only replace the axle. I don't see any abnormal tire tread wear (yet) so the alignment is probably ok. This Bigfoot is heavy. The two 3,500 lb axles are carrying 6,000 lbs. When you run these light weight trailer axles that close to capacity and hit a pothole at highway speed it would be easy to bend an axle. My axle man at AA Tire and Wheel said 5200 lb axles would fit. If I ever have to replace one I will replace them both.



I know how to grease bearings. There is a big difference in grease. I finally settled on Schaeffer's 274 moly. (you can find it on amazon or ebay). I run ten to fifteen thousand miles between bearing lube jobs.

[Raz]

Dexter says to grease the bearings every 12k miles or yearly so that's what I do. They made the axle. I take their advice.

[dmad1]

I was glad to see that on my Casita that when you pump grease into the hubs, it will push out the old grease and replace it with the new.

[ShelbyM]

Fixing to get good now!!

[stevebaz]

small diameter tires and small diameter bearings spin much faster than car tires and bearings. Trailers sit for long times sometimes for years or longer. moisture collects and isnt dried off frequently like cars being used all the time. break down or hardening grease is not a good thing for wheel bearings. But most people recommend early maintenance on trailer bearings is mainly you don't want this stuff failing on your one and only vacation each year. Much easier to maintain it in the drive way than looking for a new axle and hub out in the middle of nowhere on your vacation. Time fly's buy and ever other year maintenance becomes, I don't remember when it was done. I write the service date right on my rim. For me I try to do it early. it only costs a 1/2 day of labor and a tub of grease and new bearing seals. So for 25 bucks I sleep better knowing its done. You drive your miles and you take your chances.

Just because you greased your bearings doesn't mean your exempt from failure. There is also the don't fix what isnt broke crowd fearing your introducing a new failure point by fixing anything that doesnt need fixing.

Fearing mistakes introduced by working on something that didn't need it.

You roll your dice and you take your chances.

[mmeyer]

Originally Posted by stevebaz

small diameter tires and small diameter bearings spin much faster than car tires and bearings. Trailers sit for long times sometimes for years or longer. moisture collects and isnt dried off frequently like cars being used all the time. break down or hardening grease is not a good thing for wheel bearings. But most people recommend early maintenance on trailer bearings is mainly you don't want this stuff failing on your one and only vacation each year. Much easier to maintain it in the drive way than looking for a new axle and hub out in the middle of nowhere on your vacation. Time fly's buy and ever other year maintenance becomes, I don't remember when it was done. I write the service date right on my rim. For me I try to do it early. it only costs a 1/2 day of labor and a tub of grease and new bearing seals. So for 25 bucks I sleep better knowing its done. You drive your miles and you take your chances.

Just because you greased your bearings doesn't mean your exempt from failure. There is also the don't fix what isnt broke crowd fearing your introducing a new failure point by fixing anything that doesnt need fixing.

Fearing mistakes introduced by working on something that didn't need it.

You roll your dice and you take your chances.

I guess it comes down to how fast is "much". if you look at typical wheel sizes for fiber glass units, I think that most will fit in the 10-15 inch range With the majority likely in the 13-15" range.
Using typical load range D size tires for these rims would give overall tire diameters ranging from 20.5" for 10" wheels to 28.4" for 15" with 225/75 ties. Assuming 60mph the smallest turns at 984 revs per mile and in this case per minute while the largest spins at 710. the 10' spins 38% faster than the largest, the 12, 33%, the 13" 18% and teh 14" 8%.
My Uhaul runs 13" 185/80 and my 2002 Sonoma runs 15" 205/75. My Uhaul tires spin about 12% faster than the truck. I wouldn't consider that much faster.
The Uhaul uses a sealed bearing hub similar to those used on late 1990's early 2000's Camero and Firebird rear hubs. Anectdotally there has only been 1 or two known bearing failures in their 30+ years of existence, and one was damaged prior to failure.

[Ion]

I agree with everything said here except about the location of the manufacturers. I recall in my earlier days of stuff coming from the J. A. Pan company. That said, there has been nothing said about the type (not quality) of grease being used nor, the correct hub nut preload.

When the tire is lifted off the ground and rattles on the spindle - it is too loose and if it is difficult to get it to spin for two revolutions - it is too tight.

Dont trust you fingers to tell you the temperature. Get a digital temp meter. Check the temperature of the surrounding components, like the wheel rim, then test the wheel hub. Normally, the hub after driving for 5 miles will be about
100 * F. Bearing can run as hot as 200* but then you have to determine if it is due to dragging brakes (one hub hotter than the rest or one hub tighter than the others). Typically, I use the analogy of holding onto a cup of hot coffee.

[Stephen_Albers]

Here is an aviator perspective. Remember the old Bell 47 helicopter in the Mash movies? The industry joke was, you could always tell a 47 pilot by the grease gun in his back pocket. Some +15 grease points needed to be serviced each time before it flew. That's 50-year-old technology. Today, my Robinson R22 helicopter has entirely maintenance-free sealed bearings throughout. Every 2,000 hours all the bearings are changed for new ones during overhaul, good for another 2,000 hours.

Now, let us talk Dexter trailer bearings. Prior to 2009, Dexter manufactured a 3,500#, #10 torsion axle with SEALED BEARINGS, GOOD FOR 100,000 miles. But they discontinued it because they could not sell it. Trailer manufacturers in toto will only buy the cheapest crap available that gets the product out the door to uninformed consumers who buy only on price and are too brain dead to understand operating costs and reliability.

So the informed consumer today who wants a high reliability minimal operating cost solution has two choices. He can hound Dexter at (574-370-2661, ask for Mark Nave) to resurrect the tooling to produce the above axle with 100,000 mile sealed bearings (but, don't hold your breath). Or he can upgrade to the 5,200#, #11 axle which can be had with 100,000 mile sealed bearings in various versions for both normal and high rise boondocking applications.

New buyers who intend to move their trailers instead of using them for planters in their front yards should insist on sealed bearings unless they enjoy fiddling with greasy parts under all time of day and weather conditions in remote places. Initially, expect manufacturers to demur until enough consumers insist on quality bearings. In the interim, just buy your new trailer without an axle and have the correct one installed aftermarket. Texas Customs will do this for you.

[Darral T.]

Bought my Scamp 13' in 2010.; I have going on 11000 miles on it. NEVER pulled a bearing nor greased it. Every year when I pull, I stop after 20-30 miles and check the hubs with my digi temp. They NEVER get over 95 deg. They're no "rough" feel when I rotate the tires.

Grant it that 90% of my pulls are 200 round-trip miles, I dont intend on doing anything to my trailer unless I decide a cross-country trip. And then, I think the bearing inspection/repacking will be unnecessary.

My axle stays WELL below the rated limit. I dont pull over 62 mph 90% of the time. And why people will pull/pack EVERY year is beyond me.

I spoke with Dexter on this and they DO admit the "CYA" theory on travel trailer axles. Therefore, the CYA is especially concerning boat trailers that are submerged in water continuously. BUT, if you have ANY problem with your axle under warranty and you dont do the stupid yearly bearing-repack...they've got you and they know it!!

My trailer is NOT exposed to water except on the road. I can perfectly understand how you need to keep water out of trailer bearings that are submersed. Technically, that's what Dexter told me the reasoning of the "EZ Lube". You pump new grease in until you see it coming out the front, THEN you know you have push out any moisture/water with it.

I take no responsibility for others and their maintenance on what I wrote other than this is just MY OPINION and what I do for my trailer but I do NOT recommend this for anyone else.

Now, ALL of this doesnt take into account- defects. Bad bearings installed; not enough grease installed at Dexter; or the bearings are too tight. THEN you have no choice but to pull the bearings. But warning signs will precede the damage- abnormally hot hubs, notchiness when you spin the wheels etc.

A parting question (oh yea....I hear it now..."heavy duty bearings"...yada yada) On rear-wheel driven vehicles, how often do you pull the front wheels and inspect the bearings?

[redbarron55]

If you want wheel bearings that last you should install an oil bath bearing setup.
Oil lubed will outlast grease 10 to one, if serviced properly.
Basically bearings will give little trouble if serviced every now and then anyway.
Boat trailer bearings are a whole different thing since they are so exposed to contamination in service.
As to Chinese bearings as with everything else it all depends on the quality control of the manufacturer.
Timken bearing made in China are as good as any.
Cr*p bearings are cr*p no matter where they are made.
That being said most bearings are killed on installation when poorly done.
I remember when they started installing bearings lubed for life.
When they failed that was the end of their life.
wonder how many bearing failures are precipitated by improper installation and servicing and that perhaps benign neglect might be the right anwer.
As to temp I find that fingers work well for my purposes as 140 degrees is so hot you can't keep your fingers on it.
My bearings are usually just slightly hotter than ambient and the tires just a little warmer than that.
If I had a bearing close to 200*F I would be very worried even though the grease would be good for that temp. (assuming synthetic).
I check my bearings and tires at every stop (with fingers) and don;t worry much about them.

[gordon2]

Originally Posted by redbarron55

...
Boat trailer bearings are a whole different thing since they are so exposed to contamination in service....

So water is bad for bearings? Hmmm.. What about electric brakes?

[ntsqd]

I buy all vehicle bearings - not just trailer wheel bearings - from a bearing house, not from an auto parts store. I only buy brand name bearings, mostly Koyo (for my Toyota's), Fafnir, FAG, SKF, & Timken.

I use Redline CV-2 grease in all that are not sealed or in an oil bath.

I pack them the old fashioned way, a blob of grease on my right palm while holding the bearing in my left hand. Push the bearing into the grease until it oozes out from behind the roller retainer and between the rollers. Then rotate slightly and do it again. Continue until grease is between all rollers on that edge (inner or outer) then start over on the opposite edge.


Bearing pre-load is immensely important. How tight that nut is makes or breaks the whole deal. The best bearings and grease in the world are soon junk if that isn't set right. The axle's mfg should have a procedure for setting this.

[Ion]

Here is a suggestion for those who wish to carry a spare set of bearings;

Get a vacuum sealer

Take a bag and fill it with the grease of choice and bearings

Vacuum out air and seal

Your bearings are now pre-greased and bagged away from dirt.

You do know that it is not just the bearing that you require? You need a replacement outer race too. So; How are you going to replace that outer race, while on the side of some boondock road?

[ShelbyM]

Originally Posted by Stephen_Albers

upgrade to the 5,200#, #11 axle which can be had with 100,000 mile sealed bearings in various versions

This is interesting and warrants further research. I didn't realize such was available. I think most of us would have paid the additional cost if a modern bearing system had been an option.