Is there any "rule of thumb" for when to replace/repack wheel bearings on a utility trailer?  I normally do my boat trailers every year, as they are repeatedly dunked in salt water.  The trailer I use for bikes has a good number of miles (and tiny little 8" wheels that spin at high rpms), but the wheel hubs still stay cool on the highway, and there is no excess free play or any other signs of trouble.  Should I just leave things alone, or is there a timeline for replacing these things?  Thanks.

You replace them when you have good wear in the bearing or they get rust in them. However it does not hurt to repack them with grease every few seasons considering how fast they have to turn.

When your goin down I-80 and come up to trafic and here a noise coming from your trailer. Just pull over and remove your bearing because there dry as hell and pack them with the grease off of your front end of your truck. Works great! Just did it last week.
Mark

Just before the tire catched on fire from heat.... Had that happen to me once. Trailer had 2 tractors on it.

Grab the wheel on the top and pull and push ...if there's "play" then ...repack em' .....the bearings (that is).

I was told once a year is a good rule of thumb.



........ bahhh

+1 ^  
I service mine once a year. It gives me peace of mind when towing.

I agree with the once a year.  When my dad used to tow a lot of miles on our boat trailer, he would repack them twice a year.  It probably only takes an hour of time at most and having the peace of mind when towing 6 hours away from home is well worth it in my opinion!

Repack them once a year, or put bearing buddies on it and go every-other year.

TheBlackSheep said:

atitagain said:

Once a year is the rule of thumb in my house.

Or after a flood....learned that the hard way.

Depends a lot on how it is used and abused.  My pickup bed trailer has the original axle in it, nearly 30 years old and never been touched.  But that is not a normal trailer axle.

I don't drag my trailers around that much.  Boat generally gets a shot of grease through the bearing buddies every 3rd trip to the lake or so (about 100 miles round trip or once a year).  If I am going all the way up to Powell I put a fresh shot in before I leave.  Take them apart and inspect every 10 years or so.  Still doing good.  My other trailer (the one that I now use to haul the bike) was built in '61 by my father and grandfather.  Nearly 50 years old now.  I can't count the number of cross country trips that thing has made, kids it moved to college, moving kids out of the house with everything they own.  I finally got it a year ago.  I last packed the bearings 13 years before and it had been probably that long before that since they were last done.  the grease was actually getting so old that it was no longer the smooth creamy grease but starting to get crusty (but not chunky).  

As for my recomended maintance, I can't give you any.  I don't know if you just pull it 10 miles twice a year or are traveling 500 miles every weekend.  I would say you should pull the dust cap every once in a while and make sure that the grease is still looking good.

But do keep in mind that lots (don't have numbers but I feel over half) of wheel bearing problems are actually caused by maintance.  Incorrect installation, accidentaly contamination, etc.  I have seen neglected and abused bearings roll for a long time as well.  Jack up the wheel and give it a spin.  If it is wobbly and/or rumbles as it spins, better take it apart.

Prevenative maintance is good, but there can be too much of a good thing.  In the mines some of the air filters are not to even be inspected as inspecting them can cause more damage to the engine then just running to the designed replacment period.  Just don't do more damage then you are trying to prevent.

Interesting thread....just about to dive into repacking my bearings on the TT this morning and I saw this.   Just need to go pick up some new cotter pins and shop towels to keep things somewhat clean.

just jack up your trailer tire and give em a spin. if they sound crunchy or don't spin smoothly replace/repack your bearings.   Zerk fittings are a good way to keep fresh grease in the hub and displace water.  I trailer mostly boats and just pump the hubs full of grease until new grease comes out the back side.

snookdude87 said:

The problem with this is that when the grease comes out, you are damaging the seal, and opening it up for a worse failure.

Where grease comes out, dirt can come in.  If you have brakes on that axle, you now have a potential for grease to contaminate the shoes.

broncobowsher said:

Amen.  'Heard of guys leaving solvent in bearings before repacking (dangerously dilutes the new grease), or of blowing out solvent such that bearings get a bit worn from dry spinning, or of not repacking grease enough into the bearings.  Gotta be careful of knowing/doing enough to be dangerous.  I know that from my own mistaken-enough 'speriance!!!

chickenhauler said:

been doin this for years with hubs that go in salt water many times a week and this seems to be the best and easiest way to keep the bearings rollin.  If you replace the contaminated grease with fresh grease every now and then you have nothing to worry about.  Grease creates a good barrier itself.    Brakes can't hold up to the salt water so I don't have any on my trailers but good point.  Never been on the side of the rode with a seized hub:thumbsup: