How to Measure to Determine Correct Trailer Hub Grease Cap

Updated 07/24/2019 | Published 07/23/2019

Products Featured in This Question

Grease Cap - 1.988" Outer Diameter - Drive In

(2208)

$3.74

4" Carbon Fiber Digital Caliper

(26)

$12.23

Question:

I need new dust caps for an older trailer. Measuring across for the cap I get 1 3/4 inch. Is that accurate? Its a tandem trailer 2 wheels have caps with a zerk and 2 have just caps

asked by: Nick H

Expert Reply:

You will want to use a dial caliper or micrometer like part # PTW80157 to measure the inner diameter of the hub you have on your trailer to determine what size cap would be needed. Check out the picture I attached that shows this measurement being taken on a hub.

I attached a link to all the grease caps we offer, once you know what size you need check out the link I attached to see all the sizes we offer. The closest cap we have to what you listed is the part # F001503 which has an outer diameter of 1.786 inch.

expert reply by: Jameson C