Do Trailer Shackle Bolts Require Splines to Prevent Wear from Occurring

Published 10/30/2020

Question:

If the shackle bolts arent splined what keeps them from turning wearing out the shackle K71-449-00 I was looking for the light duty nylon bushing kit. Same kit but nylon. Thats whats on it now but I cant find that kit. I bought this 10,000lb flat trailer that the municipal Twp used a lot. It appears 18 yrs of use to wear out the shackles most of the bolts turned in the shackles. I thought the shackle holes should have been smaller going against the shoulder with the nut tightened down to keep it from spinning. Im not going to use it that much. I have two 14,000lb trailers that havent moved in 5 yrs.

asked by: Joe

Expert Reply:

In general shackle bolts turning from use over time does not considerably wear out components. As long as the bolts are greased normally the movement from standard use would not cause them to wear out. The tension of the bolt and nut is loose enough to allow the movement to happen without much friction which also allows the material to not wear out quickly either.

expert reply by: Jameson C