Do Bearings Have a Speed Rating

Updated 06/01/2018 | Published 05/31/2018

Products Featured in This Question

Replacement Trailer Hub Bearing - L44643

(2119)

$4.56

Bearing Kit for 1" BT8 Spindle, L44643 Inner/Outer Bearings, 34823 Seal

(3392)

$18.46

4" Carbon Fiber Digital Caliper

(26)

$11.93

Question:

I think I have this size bearing on the axles of a 1973 camper I bought, i am not positive for I am not home and cant measure it right now, I was able to get replacement bearings at a parts store, the old ones are not damaged, just need to be cleaned and repacked, I know the spindle on the outer edge is smaller than 1 inch, the inner bearing is a standard 3500 ib bearing, is the outer bearing cable of with standing high speeds? Max 70 mph?

asked by: Martin S

Expert Reply:

If you have a standard 3,500 lb axle and the spindle is about an inch in diameter then the correct inner and outer bearings for you are # L44643 which have a 1" inner diameter exactly. This can be found in the kit # BK1-100. If your spindle is smaller than an inch then you probably have a smaller spindle that is not standard (which would make sense on an older trailer).

When choosing replacement bearings, it is always important to measure the spindle where the bearings ride to the 3rd decimal place (example 1.234) with a digital caliper like part # PTW80157.

With that being said, bearings don't have a speed rating. As long as you keep them well-greased and you don't exceed the speed rating of your tires you don't have to worry about the bearings (granted they are in good condition).

expert reply by: Jon G