How to Measure a Trailer Wheel Pilot Hole to Choose a Replacement Center Cap

Updated 02/03/2014 | Published 01/31/2014

Products Featured in This Question

Karrier ST225/75R15 Radial Trailer Tire - Load Range D

(2299)

$142.32

Question:

I have lost one of the wheel center caps on our horse trailer and want to buy a replacement. However, I have no idea what pilot size means or how to measure for it. what do I need to know to order the correct cap? thanks so much. My daughter has the trailer at college, so if I need to know the tire type/size, I recently ordered a spare from you...can you look up the tire info from your records?

asked by: Toni L

Expert Reply:

The pilot hole on a wheel is the big center hole right in the middle of the wheel. It fits over the hub.. It can be tough to measure these with the wheel still on the trailer so you will want to remove the wheel and then it will be easier to measure. The best way to measure it would be to use digital or dial calipers.

I can look up the tire you previously ordered, # AM10256, but since the wheels that the tire fits could have different size pilot holes I cannot go by the tire size alone. I really do need that measurement on the actual wheel. It is likely to be 3.19 inches of 4.27 inches but could be different.

Once you do know the measurement you can look through the caps, see link, to find one that will fit. Or tell me the measurement and I can make some recommendations.

expert reply by: Michael H