Bearing size

What's the easiest way to identify what size bearing kit I need? I just purchased a used Bass Tracker on a 1986 Magic Tilt trailer. I changed them out on a bass boat I had 10 years ago with no problem, but it was newer and I was able to obtain all of the necessary information from my trailer manufacturer. The Magic Tilt website does not have this information.

Thanks for your help.

I would do 1 of the following 2 things (probably the latter)....

Mic the hub and the spindle and purchase accordingly.

Take it to the local Henderson's (auto parts and more store) and ask them what bearing I need and buy 'em.

Thanks! I saw where Academy carries for or five different kits, with the only identifying feature being the outside diameter of the spindle. I'm curious if that's all that would be required is a measurement (although the difference in 1" and 1 and 1/16th" might be difficult to tell?) Do the various spindle sizes always directly correlate and relate to a particular bore size (i'nn need this info to purchase the correct size Bearing Buddie)?

1 inch and 1-1/16" bearings use the same size race. Take one hub apart the bearings and races have numbers on them.

Easiest way (and to be absolutely sure), is to pop the hubcap, then remove the cotter pin, castle nut and washer. Pull out on the tire and rim just enough that it loosens the bearing, and be ready to catch it with a rag. Use a vernier caliper and measure its ID.

I'm a big fan of measuring them due to the alarming regularity with which manufacturers change sizes of things on the line. My Coleman popup came with 2 different sized spindles from the factory - 1" on the right and 1.0625" on the left. Measuring is always a good idea, and you can get a reasonably good caliper at most parts stores or Harbor Freight for around $10.

If you aren't comfortable with measuring, you can take them out and actually identify the bearing size by the part number. Take the numbers off of the cone (the part with the rollers), not the cup.

Trailers usually use tapered roller (Timken type) bearings, so your first digits will be "32" or "032". Then your next digit (0-9) will be the series. Then you'll have 2 digits indicating the bore size. Take these two digits and multiply times 5, and you'll have your bore size. For example, a 32305 bearing would be a tapered roller (32), medium duty (3), 25mm bore (05x5). Sometimes you'll find an "R" in the prefix indicating an "inch series" bearing, which are an older system and usually require looking at a chart to get the dimensions.