Threaded collars on coilover suspensions or lock rings on fuel pump assemblies do not have standard hex heads. A spanner wrench features a curved jaw with a hook or pin at the tip. The hook slides into a notch on the ring, allowing you to turn it. Some models are adjustable to fit various diameters. Using a spanner prevents you from damaging the soft aluminum collars by trying to turn them with a hammer and screwdriver. Keep the hook fully seated in the slot as you apply force to prevent it from slipping out.
Mechanic Glossary
Spanner Wrench
A wrench with specialized pins or hooks designed to engage slots or holes in lock rings, locknuts, and suspension collars.
Frequently Asked Questions
The most common are hook spanners for notched collars, pin spanners for holes on the face of a nut, and face spanners for recessed rings.
This happens if the wrench is not held flat against the collar, or if the threads are dirty. Clean the collar threads with a wire brush and spray them with lubricant before turning.
No. The weight of the vehicle places heavy tension on the spring collars, making them lock up. Always jack up the vehicle to take tension off the springs first.
Measure the outer diameter of the collar. Most spanners list their range, such as 68mm to 75mm.