Winter is coming, and you need to install your snow tires. In case your vehicle has lock bolts or security nuts and you cannot remove them using the key tool or you lost your key tool, this Instructable is for you. For those living in a more temperate climate, having lock bolts on your wheels while having a flat tire on the side of the road could be a disastrous and expensive experience, so please consider removing them.
I bought a used car in May, and when came time to change the tires, I noticed the previous owner had installed one lock bolt (or security nuts, with a unique pattern) on each wheel. He gave me the key socket to remove the bolts. I did not pay too much attention back then, not having to remove the wheels until now, to install winter tires. Then my problem started. The previous owner, or his mechanic had over-tightened all the bolts with an impact driver, at maximum pressure. On my first attempt to remove the lock bolts, I noticed they were over-tightened so much, that the key socket got broken and slipped, and became useless. Thinking the socket was the cause, I went to the dealership, and their mechanic tried with their own set of key socket (better quality, I assumed). That socket got broken as well. The mechanics mention they could do the removal, but it would be an expensive job and I would have to wait one week.
Doing a bit of research, I found a bolt extractor from Irwin Tools, p/n 53915 Irwin 13/16"- 21mm, which seems to do the job. Trying to get this item though was not easy, because most car par dealers / hardware stores do not carry it stock. They carry the smaller versions of the tool. Going to my local NAPA auto parts store, I found a 21mm extractor (the size of my wheel bolts), part number 62798R4, which has a left-threaded conical pattern on one end, and a 1/2" square socket hole on the other. I used this tool as-is, and after 5 attempts, hammering it down several time on the lock bolt, I could not remove even one. I thought the battle was lost, until...
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Step 1: The Solution, and the List of Material Needed
The solution came after many unsuccessful attempts, and worked. I was able to remove all 4 lock bolts without damaging the alloy rims of my wheels. One of the trick that mechanics use to remove stubborn bolts is heating the bolt with a propane torch to help loosen it up. I did not want to try this, fearing it could damage my alloy rims, especially considering that the bolts are deeply recessed, and most of the heat will end up on the rims. Instead, I put my faith on a a simple physics propriety, which is that metal heated will expand, and contracts when it is cold. So wait for a cold day, early in the morning, with the car parked outside, and gather the following items.
- A 21mm socket, bought at NAPA auto parts, described above. Part number 62798R4
- A propane torch
- Tongues to hold the socket
- A 5 pound hammer
- A breaker bar, with 1/2" square drive, matching the socket
Step 2: How to Finally Remove the Lock Bolts
Be sure the outside temperature is near 0C (32F), and every part of the car is cold. Using the blow torch and holding the socket with the tongues, heat the socket for about 1 minute. This expands the metal in the socket. Then swiftly, put the threaded part of the socket on the lock bolt and hammer it about a dozen times with the 5 pound hammer. You want precision, and you aim for the center of the socket. To cool the socket down, use 2-3 ice cubes. This makes the socket contract and adds enough friction, combined with the left-thread and conical pattern of the socket, to prevent slippage. Using the breaker bar, apply uniform force and keep it perpendicular to the socket. At one point, it will rotate, you will probably hear a cracking sound indicating success. If the socket rotates around the locking nut, and it is still stuck, try again, heating the socket a little longer, and hammering a bit more. Be patient, and you will be rewarded.
Step 3: Heating the Socket
Step 4: Then Swiftly Put It on the Lock Bolt, and Hammer It
Step 5: Cool It With Ice
Once you removed the bolt, it will probably be stuck in the socket. At this point, you can either heat the socket again and put the bolt in a vise and rotate to pull it off. Or you can use a large punch or a 3/8" rod of metal and use it through the 1/2" square opening to punch out the bolt using a hammer.
Step 6: All 4 Bolts Removed, It Took About 1 Hour From Start to Finish
Step 7: Conclusion
Congratulations, you have done it. Now, what to do with the lock bolts... just in case you would be tempted to put them back, DON'T. These days, a lot of cars have alloy wheels, and unless you drive an expensive car or live in a dangerous neighborhood with a lot of theft, the lock bolts are useless. Plus, if a thief has spotted your car, chances are he has the knowledge and the tools to pull off the lock bolts much faster than you.
Do like I did, they are now in my trash bin!!