Measuring Spindle for Replacement Oil Seal

Published 03/19/2019

Question:

Hi, I have an old trailer with a straight 1inch spindle that is missing the inner grease seal on one side and the other side seams to be too large so not real. Is the inside diameter of the inner oil seal supposed to match the size of the spindle? If so, how does the bearing tighten down? Thank you,

asked by: Ben

Helpful Expert Reply:

The seal will be a similar size but it all depends on the spindle itself as to the actual size. It should have a tight seal so you don't leak oil but most systems use grease which also needs a good seal. The best way to determine the correct fit for your specific axle is to use a digital caliper to measure the spindle at that location. I've attached a photo to assist.

Once you have that measurement you will have the inner diameter for your seal and then you will measure the back of your hub to get the outer diameter with that same caliper. Precision is important. If you want to go to thousandths versus hundredths, a digital caliper will give you that additional precision.

I've attached the page to all your seal options to assist.

expert reply by: Jason S