Bolt and Lug Nut Torque Calculator

Industry formula: T = K × D × F with F = 75% of proof load. Torque wrenches are ±25% accurate at best — verify your specific bolt against OEM service data.

Recommended torque
Wheel / suspension range
ft-lb
88
Nm
119
in-lb
1056

M10 × 1.5 Class 8.8 dry: tighten to ~37 ft-lb (50 Nm). Use a 3/8" drive torque wrench. Allow ±25% wrench accuracy — final pass at full spec.

3/8" drive (15–80 ft-lb) — covers most engine accessories

Reference values, not safety-of-life data. Torque wrenches are ±25% accurate at best (per Fastenal / SAE engineering convention). Industry T=K×D×F formula uses 75% of proof load as default clamp force. Always verify in your owner's manual or OEM service data, and use a star pattern on lug nuts (two passes — half-spec first, then final spec). Mike Reeves is an ASE Master Technician, not your dealership service writer.

Bolt & lug-nut torque calculator by RevRated  ·  Reviewed by Mike Reeves, ASE Master Technician