What is the Difference Between Left-Handed and Right-Handed Threads?

Updated 07/14/2021 | Published 07/12/2021

Question:

For rear center cap hub why right hand or left hand thread

asked by: JAMES T

Expert Reply:

Even though most threads on bolts use right-handed bolts/nuts, some special scenarios warrant a left-handed thread. When wheel accessories like the Phoenix USA Rear Wheel Center Cap - 8-1/4" Hub Diameter - Center Hole Mount - Left Thread # PXQ1020L use a left-handed thread, it is to avoid the added torque from bumps and rough terrain on your wheels. With these forces, right-handed bolts/nuts tend to come loose from those particular movements. For a hub cap, it is recommended to use a left-handed bolt/nut if the option is available (like it is on the hub # PXQ1020L).

Also, it is important to note that the threads are from the bolts that hold the cap in place; not on the cap itself.

expert reply by: Bob C