Master Lock Locks & Locksmithing - Page 2 - Recent Questions, Troubleshooting & Support

If it has a key hole in it then you can take it to a lock smith and they can open it and reset the combination for you.

Call Master Lock or search on You Tube!

Have 5400D Master Lock. Know combination, but it will not open. Can someone help me?

Check the MasterLock web site to see if they still offer to provide for forgotten combinations. Some years ago I got a combination for a standard rotary dial lock by providing the usual identification information plus a photo of the lock showing its serial number.

You have 10,000 combinations to go through. Best to cut if off and bring it some place comfortable to try out all of the combinations from 0000 to 9999. Or take it to a machine ship and have someone grind the thing open.

I just unlocked a 1534 4-digit lock I couldn't open for 2 years. I found the info online. Use a flat blade to spread the wheels apart slightly and look for the red mark on each wheel. There were only three metal tabs on each wheel on mine so if this is the same on yours and you can't find the tab with the red mark, worst case senario would be to record each number shown at the mark when one of the tabs is lined up. It will take 3^x turns max to find the combination without locating the red marks. For 4 wheels, that is 3x3x3x3 or 81 possible combinations. For 5 wheels, it would be 3x3x3x3x3 or 243 possible combinations. If you can find all but one red mark, line them up with the mark on the lock and go through all digits on the one you couldn't find. Shouldn't take too long. I tried to unlock mine by brute force (every possible combination of 10000 choices) and ran out of steam less than half-way through. That was with only 4 wheels and 10 digits each.

Take your lock if at all possible to a locksmith to avoid any service charges. Don't bother with the manufacturer as they will not give combos out for security reasons. Your lock will have a serial # that your locksmith can access and find out what your combo is. If you can't bring the lock to the locksmith check what their service charge is. It might be cheaper to cut it and replace it than to call the locksmith out.

To set a new combination: The initial combination is set at the factory to 0-0-0-0 1. Open the compartment door 2. Push the reset lever left and down. The lever remains in this position 3. Rotate dials to your desired combination 4. Push the reset lever, up and right, back to the original position 5. Close the key storage compartment door 6. Scramble the combination dials to lock the door and conceal your combination 7. Close the shutter door

No, no, no, no. That won't work. Otherwise, anyone could get the serial number, get your combination, and open your lock.

www.masterlock.com/.../5400D_Instructi...

You'd need to be a bona-fide locksmith to buy a code book. Most any locksmith can look up combinations. I know I've looked up a few.