Friends and neighbors - it's that time of year. Everyone with a road rig is looking it over and deciding what needs doing to make it safe and shipshape. One thing you don't want to miss is an in-depth bearing repack, and brake inspection.

You will find that trailer wheel bearings are not at all different than the bearings on stub-axles of truck and car front wheels. There is a large inner bearing, and a smaller outer bearing. They are tapered roller bearings, and require grease repacks every so often - EVEN IF YOU HAVE "BUDDY BEARINGS".

Boat trailer type buddy bearings are the kind with a spring packed reservoir that holds grease under constant pressure so as to prevent water intrusion...

They still need periodic adjustment, and it doesn't hurt to look them over with a calibrated set of eyeballs.

In the process of removing the brake drums/bearings you also have an ideal chance to see the brake shoes and check for problems inside the brake drums.

*Are the brake linings wearing thin on the shoes?
*Are there broken or messed up wires inside the drums?
*Is there a lot of rust, scoring, or pitting on the drum surfaces?
*Do the magnets and linkages move freely?
*If someone activates the brake controller, do the magnets grab a metal object held next to them? (YES! This is a very good way to test them)
*Do you see a brake adjustment, and if so see how it works? Does it move freely, or is IT rusty?
*Are there signs of rust or damage to the bearings once they are cleaned?
*Does the old grease look contaminated?
*How do the inner seals on the drums look? Do they need replacement?

These wheel bearings are adjusted and maintained just like the ones on your trucks front wheels. On reassembly, the castellated nut should be tightened down just a bit more than snug, and the drum rotated while the nut is being tightened. The way I was taught, once the nut is "SNUG TIGHT", the nut is then backed off about an eighth of a turn to allow for heat expansion as the wheel rolls. Failure to allow for this expansion factor can cause fractured races and disintegrated bearing needles/rollers farther down the road
("Ain't no shade tree guys in this garage!!!"). That method was taught to me thirty years ago, and is still true of any wheel bearing...

At this point - find a position where the cotter pin can be inserted through the castle nut and hole in the stub axle end. The correct way to install a cotter pin (or "COTTER KEY") is to bend ONE BLADE of the cotter pin up over the nut, and clip off the other one. Either way - snip off any extra length with a pair of dykes.

("HEY! Get those Ladies out of my shop - what are you thinking?" )

*If you think about it, cotter pins are the original "Safety Wire System"

*I generally will try to stuff extra grease into a hub any way I can, just as extra insurance. As long as the dust cap stays on, all is good. What you DON'T WANT is to have bearings running DRY!

*There is no replacement for GOOD QUALITY GREASE. Since this is an often neglected area, I go RIGHT TO THE WHITE LITHIUM GREASE CAN (you bet I do!) because it doesn't break down over time and it sticks to what it is put on. Pure "White Lithium" grease can be found at any auto parts store - if you have never seen it before GO LOOK. You may have never seen a grease as effective as this stuff before...

*Be careful not to ding or deform the dust cap putting it back on. DO make sure it is all the way seated. A rubber mallet works well for that, you can also fold a rag and use that as a pad to help prevent hammer-hit dings. It doesn't say in the bible exactly when God created "shop towels", but no garage is complete without them in my belief...

MORE QUESTIONS? Ask...

As my NAVY instructors always said:
"The only dumb question is one you never had the guts to ask"


~GREYWOLF

 

Thanks for the reminder. I repacked the bearings on my horse trailer a month ago. Easy job just a little messy. While your at it look really close at your tires. Even if they look good if they have some years on them they will dry out. I replaced all 4 tires while I was at it. Now I am good to go for another year.

 

Good tips, Wolfie -

When it's time to replace bearings and races, use a brass drift punch to knock out the races; no scoring of the hub that way. Also, double-lip seals on boat trailer spindles are good insurance against water intrusion.

Steve

 

All of this is good information and protection. We need to be safe out there - especially with anything that costs as much as a fine RV or horse hauler. I don't even want to think about a horse trailer rollover.... That would keep me up at night!

I HAVE seen (censored) RV techs that thought when a nut was snug you had to FORCE IT TIGHTER so that the cotter key would line up... I hope that when I got done reaming them out they never forgot what I said to them!!!

~And yes, those are the "labor" people that they charge $95.oo an hour for at RV dealerships...

I guess I have a lousy opinion about them. Thank the Lord I saw it from the inside, and not at my own expense.

*THIS TOO needs to be added to the "STICKY" at the top of the forum. I think that being what it is it's a critical one.

 

Gray... very good advise. I just put all new bearings and seals on both axles. $185 for bearings,races,seals. plus a couple of $ for beer to cool me off. Our local RV shop has stopped selling new rigs and is now only parts and service.

 

I can't emphasise enough that a tech needs to be aware of heat expansion - and ought to be quizzed on that point as to how they tightened the bearings up. A SIGNED STATEMENT would be even better!!!!

I don't trust things like that on my own wheels to ANYONE AT ALL..

It has been my observation that in an area where nepotism is the general rule - IGNORANCE is rampant. None of these sorry want-to-be's is certified.....

And the certification program itself I found holes in...............

RVIA is rife with disinformation - they are incorrect on many points dealing with electrical and electronic matters. I HAVE SEEN THE TEST QUESTIONS AND ANSWERS

I've got news, many of them are wrong.

I know what I am saying, and what I am talking about (two different things - one is an accusation, the other is professional knowlege).

I would not trust a DOG HOUSE to be repaired by most RV dealers. Honest to God truly

 

Good points Greywolf. I go over my car hauler every year before inspection. I also keep a "log" of miles used. My smaller trailer does not need insp so I have to remind myself to check the bearings.

 

A "LOG BOOK" is an excellent idea! No trailer yet made has it's own odometer.