what size wheel bearings do i need?

[Epoweredrc]

Okay so as someone pointed out to someone on another site wheel bearings on a trailer are very important... We have a utility trailer that is around 15 years old we have never replaced the bearings on it.. and my hi lo trailer i'm sure no one has ever replaced them cause that is just my luck.. well if you have read my other posts i am in the process of turning my camper into a enclosed trailer for my Radio control plane hauler. so its going to be getting some miles put on it and i want to make sure its in great shape to do so.. i have brand new tires on it.
I looked on advanced auto site and see there driffrent sizes.

Thanks for the info

 

[piperjim]

I'd take the bearings out and clean them, and take them to an auto parts shop and let them insure you get the correct replacement. Bearings will have the part or model number on them, but I'd take them in just to be sure.

 

[Epoweredrc]

Thanks..it be a few days but I did want to figure out everything

 

[piperjim]

Be sure to take the rear seal in, too.

 

[RCREYES]

Northern Tool has a pretty wide selection as well. If they have a store where you live, they have a board where you can match them up.

 

[maestro123]

use id and od dial indicators find id and od of brake drum or old ones, ouside and inside and then measure axle od, and depth of bearng w/ drum on. should do it!

 

[Epoweredrc]

thanks everyone... is there a good way to know if you need new ones? or would greasing the old ones help at all? thing is not knowing when it got grease or if ever changed it is 37 yrs old.

 

[Treeclimber]

Epower, When I remove these bearings, usually one at a time, I clean with gas, blow it dry with the air compressor. If the bearing is scored, burnt looking or rattles TOO much, take it to NAPA and see what they think. If the first one is bad, you can bet the rest will be the same. Purchase as necessary, including the rear seals. If you'll feel safer, replace them all and the seals. Pack with the best wheel bearing grease on the shelf. If unsure how, youtube helps. I use a small wooden block to drive out the inner bearing/seal. Don't try to save that inner seal, not worth it.
Tree

 

[maestro123]

yeppers!

 

[JIM L-HILO]

Epower, When I remove these bearings, usually one at a time, I clean with gas, blow it dry with the air compressor. If the bearing is scored, burnt looking or rattles TOO much, take it to NAPA and see what they think. If the first one is bad, you can bet the rest will be the same. Purchase as necessary, including the rear seals. If you'll feel safer, replace them all and the seals. Pack with the best wheel bearing grease on the shelf. If unsure how, youtube helps. I use a small wooden block to drive out the inner bearing/seal. Don't try to save that inner seal, not worth it.
Tree

If you have a bad bearing , when you replace it you should replace the bearing race also. If you are on the road and have a bearing go bad then it would be ok to replace the bearing in that emergency but get the races replaced ASAP. I have never seen bearnings, races, or seals that did not have the part numbers stamped or printed on them. On the seal the P/N may be on the rubber part of the seal. Hard to read and you may need a magnifying glass to read it. I carry a set of inner and outer bearings, races and seal as we travel.