Locking Wheel Bolt Removed
My office buddy (Paul) and I recently changed the brake fluid in his car. While trying to remove one of the wheels we discovered that the locking wheel nut was extremely tight and we severely damaged it in the process of trying to remove it.
Normally, the nut looks like this:
The toothed key nut with a unique pattern of ribs and notches slides inside the keyway of the locking bolt on the wheel.
As the bolt was so tight, we used an extension bar with the the socket set. Unfortunately, as you can only apply force in one direction, this pushed the key downwards rather than just twisting the bolt. This caused the sides of the locking bolt to deform and get wider.
The result was a bolt firmly wedged in the wheel which now looked more like the dotted line in the diagram below.
Deformed Lock Bolt
We purchased a locking wheel nut removal tool from Halfords which is like a socket set but with a hardened reverse-screw thread instead of a hexagonal key. The principle is that as you try to undo the bolt, the socket screws tighter around the outside of the locking bolt and so gripping it. But as the outside of the locking bolt had deformed so much and was now flanged, we were unable to get the removal socket around the outside of the lock bolt despite lots of hammering, levering and deforming.
Re-forming Lock Bolt
Finally, we stumbled upon a method to restore the bolt to its former shape. We hammered an oversized impact socket around the bolt, then used an air impact wrench to spin the socket around the flanged edge. Gradually this smoothed the flange forcing the bolt back to its original shape.
This got us back to where we started - a locking bolt that was incredibly tight, and which we couldn’t use a long extension to undo. How could we get enough torque to undo the bolt without damaging it?
We tried lots of WD40 and an air impact wrench, which provides the rotational torque without any of the lateral force. But even on full pressure (110 psi) it was unable to crack the bolt’s grip on the wheel.
Finally, we came up with an idea to give us bags of torque with little down force. A 4-way wheel wrench seemed good, but was far too unstable when we applied even a bit of force. However, by stabilizing it with an axle stand, it stayed firmly wedged in the socket, and we removed any lever effect which damaged the bolt last time. Now we could stand, jump, and pull on the 4-way wrench without it damaging the bolt.
4-way wheel wrench with axle jig
The bolt cracked within seconds. It’s now been replaced by a regular bolt - much easier to remove!