Grease Seal Fit based on Inner Diameter and Outer Diameter

Published 09/30/2016

Question:

Example: What should the size of the seal be if you actually measure 1.250 on the ID and 2.00 on the OD. I do not know how much smaller on the ID you are allowed and how much larger on the OD you are allowed.

asked by: Steven S

Expert Reply:

When you measure with a caliper, use the inner and outer diametes to help you find the right seal. On TruRyde's Double Lip Grease Seal, # 34823, we give you measurements that are extremely close to what you sent in your question. The very slight variance could be the wear on an old seal and the compression to put the seal in or take it out of the hub. These seals are a very snug fit to prevent grease leak and keep debris out of the bearings, so there really isn't much play.

You can measure the inside edge of your hub with the caliper and the inside spindle to confirm the measurements as the precision of these measurements are within thousandths of an inch. I've attached a photo to help. The outer diameter of a grease seal should be a around 2-4 thousandths of an inch bigger than the inner diameter of the hub bore and the inner diameter of the grease seal should be about 2-4 thousandths of an inch smaller than the grease seal seat on the spindle.

The grease seal you mentioned, # 34823, is a common grease seal for 2,000 lb axles and that is likely what you have. There isn't any grease seal I'm aware of that is exactly 2 inches outer diameter.

expert reply by: Jason S