I'm reworking a 16 foot trailer that I occasionally use to haul equipment. I've repainted it and currently painting the wheels. I plan to re-wire and add LED lights. I pulled the hubs off to inspect and repack the wheel bearings. The spindles were fine with no scaring. I pulled the front bearing out of the hub and repacked but left the rear bearing and seal in and just added grease to them and inside the hub. I put them back on and they spin freely with no noise and no wobble. So my question is how do you know it is time to replace the bearings? It all seems to be fine, but since I'm at this step, I wondered should I go ahead and replace them. Thank you.
Wheel Bearing Question
- Thread starter Ridger
- Start date
As long as grease is present,bearings are adjusted correctly and they arent noisy then you should be fine. If a bearing does start getting noisy its time to replace them all. Depending on the retainer it can be a little difficult to adjust them just right. Best setup is cotter pin and castle nut. I find some retainers force you to adjust them too tight my .02.
My pet peeve-dust caps. Just grab them with a large pair of slip joints and crush caps to get a grip. Pound em on with the biggest hammer you got. Yup, drives me nuts.
There are dust cap pliers to aid in removal,i use a screwdriver under the lip to work cap off. A piece of pvc pipe works to drive them back on. Or,same screwdriver and a small hammer on lip to drive back on.
Lose the cap and bearing fails in short order.
My pet peeve-dust caps. Just grab them with a large pair of slip joints and crush caps to get a grip. Pound em on with the biggest hammer you got. Yup, drives me nuts.
There are dust cap pliers to aid in removal,i use a screwdriver under the lip to work cap off. A piece of pvc pipe works to drive them back on. Or,same screwdriver and a small hammer on lip to drive back on.
Lose the cap and bearing fails in short order.
85Hokie
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TJ covered all the right things
....a good pair of bearing buddies goes a long way too. Always greased and you can tell if the grease is low too.
Sometimes hard to get the perfect size - there are several sizes depending on what diameter yours are.
https://www.amazon.com/Reese-Towpow...&qid=1495023077&sr=1-3&keywords=bearing+buddy
Daren Todd
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Like TJ said. You should be fine. Usually when I have a trailer jacked up, I will spin the tire. And feel for any grabbing and binding. And then try to move the tire sideways. If a bearing is going out. Usually you can feel it either grabbing or you will get some sideways movement. You will also get sideways movement if the nut isn't adjusted correctly. So if you get sideways movement, check the nut first. Is that doesn't take care of it, then replace bearings.
Usually when I get a trailer that is new to me. I pull the dust cover. Then grease until I see grease come out the front bearing and coat it. Then you know there isn't any water or moisture in between the bearings. Then about every 6 months of use, I pull the dust covers and repeat the process and wipe out the access with a rag. If trailer is rarely used. Then I do it once in the spring time
Usually when I get a trailer that is new to me. I pull the dust cover. Then grease until I see grease come out the front bearing and coat it. Then you know there isn't any water or moisture in between the bearings. Then about every 6 months of use, I pull the dust covers and repeat the process and wipe out the access with a rag.
If trailer is rarely used. Then I do it once in the spring time 
To add to what has already been said, when you service the bearings, look at the roller ends to make sure that the ends of the rollers are not up against the steel cage that retains the roller. Most, though not all rollers have a relieved dimple on the ends. When a bearing is held down by the nut, the natural tendency of a worn bearing is to rub against the cake Window as they wear. It can roll a burr of steel up on the cage window end along the smallest diameter side of the tapered bearing. Seeing that should be a sufficient warning to not over-tighten the nut and replace the bearing respective bearing if the condition exists.
Wheel bearing service goes like this:
Disassemble and remove bearings. Clean in Stoddard solvent, not gasoline. Dry bearings and inspect. Look for any signs of wear or failure of the bearing surfaces. Also clean and inspect the hubs and races. Clean and inspect the spindles.
You want to look for brinelling, fretting, cracks, discoloration, bent or damaged cages, rust.
NSK has a very good page on bearings here.
If everything looks good, pack the bearings with a good quality wheel bearing grease. I prefer the kind that is very sticky, that kind of strings as you pull it apart. Don't use chassis grease.
I learned to do this by hand, a small amount of grease in the palm, and briskly scoop into it with the bearing forcing the grease into the assembly while rotating the bearing. You know it is done when the grease comes out the other side.
Or you can get one of many various packers that use a grease gun or have a lever and reservoir of grease to force the grease in. They work great, and are a bit quicker than the manual method, but just as messy.
Reassemble, adjust and go.
If you can't get the dust seals off without damage or distortion, replace them. A trick I learned is to remove the outer bearing, replace the nut, and then use it to catch on the inner bearing as you pull the hub off. If you do it right, it pops the seal off cleanly. They can often be cleaned, and if not damaged reused, just pack the backside and lip with grease and reinstall.
Also use a new cotter key every time. Even if you have just put everything back together and realize that you forgot to put the seal on and have to pull it apart, use a new key.
One last point. Bearing adjustment. How tight or loose a wheel end bearing is set depends on the intended use and how it is lubricated. Heavy trucks and equipment have bearings that run in gear lube, and usually are set up tighter, with little or no endplay.
Bearings on light utility trailers that run with grease are usually set up with some endplay. It isn't much, and I think there is a spec for it, a few thousandths of an inch or something. After more than 40 years of taking them apart and putting them back together, I have developed a feel for it. After performing a wheel end service on a trailer, I take it out for a run, 5 or 10 miles. Stop, check the hubs, feel for how warm they are. If the hub is too hot to leave your hand on the bearing is too tight. If you grab the top of the tire and push/pull you should barely be able to feel the endplay. If you can hear it clunk, it is too loose.
Remember to retorque the lug nits after 50 miles or so too.
If in doubt,, wheel bearings are cheap compairing to sitting along the road some place, carry an extra set for each wheel.. and the bearing buddies are a super idea I had them on every boat trailer I owned and never lost a bearing
Bearing buddy is a good product,that on rough gravel roads tend to fall out.carry a spare. Bad seals and missing dust caps are what cause trailer bearing failure. I dont want to advise anyone on setting wheel bearing preload,but i will say too loose is bad, too tight is worse.
On a spindle nut that moves smoothly,finger tight while spinning hub is usually enough. Smaller bearings require less preload. 1-1/16"spindle for example.
1-3/8" spindle could use 1/2 flat on nut past finger tight.
Had a car towed in, rear wheel bearings just replaced and both locked solid. Spindle nuts were both so tight i needed 1/2" breaker bar to loosen. Had to replace axle and hubs due to a lack of experienced diy-er.
If you are servicing brakes outdoors,keep everything clean,including the tools. A few grains of sand will cause premature failure.
The warm hub thing is something i often check,a few miles and stop, check load and tires and hubs. Its an easy routine and will save a lot of grief. Especially retightening tie-downs on load.
On a spindle nut that moves smoothly,finger tight while spinning hub is usually enough. Smaller bearings require less preload. 1-1/16"spindle for example.
1-3/8" spindle could use 1/2 flat on nut past finger tight.
Had a car towed in, rear wheel bearings just replaced and both locked solid. Spindle nuts were both so tight i needed 1/2" breaker bar to loosen. Had to replace axle and hubs due to a lack of experienced diy-er.
If you are servicing brakes outdoors,keep everything clean,including the tools. A few grains of sand will cause premature failure.
The warm hub thing is something i often check,a few miles and stop, check load and tires and hubs. Its an easy routine and will save a lot of grief. Especially retightening tie-downs on load.