What Size is the Should Bolt Comes in the Replacement Roller Wheel and Shoulder Bolt?
Updated 05/13/2026 | Published 05/11/2026
Question:
Is the shoulder bolt for the C79UR replacement wheel assembly an M8 1.25 or an M8 1.0
asked by: Mannie S
0
Expert Reply:
Hello Mannie,
The shoulder bolt for the Curt # C79UR replacement wheel assembly is effectively an M8 x 1.25 thread.
Curt lists it as an “M8 x 25 grade 10.9 bolt” without specifying pitch. In ISO metric fastener standards, when the pitch is omitted on an M8 bolt, that indicates the standard coarse pitch, which is 1.25 mm.
What model hitch are you trying to repair?
expert reply by:
Kate F
0
Product Page this Question was Asked From
Replacement Roller Wheel and Shoulder Bolt for Curt A-, E-, Q-, or R-Series 5th Wheel Hitch - Qty 1
- Accessories and Parts
- 5th Wheel Hitch
- Head
- Roller Adapter
- Roller Wheel
- A-Series
- E-Series
- Q-Series
- CURT
more information >
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Mannie S.
5/12/2026
Repairing a broken bolt on a Curt, A16 hitch. The bolt sheared off right at the point where the threads meet the shoulder. I had to drill the thread threaded part out and I’m going to retap the hole to make sure it fits correctly.