TorqueSpec
Bolt torque database
HomeComponent Torque Specs

Torque Specs by Component

The fasteners people actually look up — drain plugs, spark plugs, head bolts, brakes and valvetrain — plus a quick answer for any bolt size.

Engine, Brake and Driveline Components

Looking for wheels? Lug nut torque by vehicle covers 102 models across 19 makes with bolt pattern, thread size and socket for each.

What Torque for a Metric Bolt?

Every property class for one size, side by side.

What Torque for an Imperial Bolt?

Grades 2, 5 and 8 for one size, side by side.

Common Questions

What torque should I use if there is no published spec?

Fall back on the size-and-grade value for the fastener. Identify the diameter and the grade marking, then use the metric or imperial chart on this site — those figures come from ISO 898-1 and SAE J429 with clamp load at 75% of proof load. Treat them as a starting point, not as an override for a manufacturer figure.

Why do component torque specs differ from bolt-size charts?

A bolt-size chart assumes a steel bolt clamping steel. Real assemblies often clamp aluminium, plastic or a gasket, where the joint yields long before the bolt does. That is why a valve cover bolt takes 7 ft·lbs even though an M6 class 8.8 bolt could take twice that.

Are torque specs in dry or lubricated condition?

Unless a manual says otherwise, assume dry, clean threads. Oil or anti-seize cuts friction so the same wrench setting produces roughly 20–30% more clamp load — enough to strip aluminium threads or yield a fastener.

Grade Charts