numbers for spaire tire lock

[Denny J.]

The numbers on the lock are 3912416 could I get a year for that please the key is a "B"

[Joe L.]

Re: numbers for spaire tire lock

denny-----

GM #3912416 is a SERVICE-only lock assembly first available in mid-1967. It replaced earlier lock assembly, GM #3867322, and SERVICE 1963+ Corvettes. It was used through the 1979 model year. It is very similar, if not identical, to the lock assembly used in PRODUCTION for 1968-79. It is also very similar to the lock assemblies used during the 63-67 period but may vary in minor ways.

These units can usually be re-keyed for any 63-79 original key code.

[Jack H.]

Keyway encoding changed...

in five year cycles. A/B keys were first used in 1967, C/D keys followed in 1968, Etc. So, a spare tire lock with 'B' keyway encoding works for 1967, 1971, 1975, 1979...

[Peter L.]

Re: The old math!!!!!!!!!!

Jack - Your math teacher might just have to have a talk with you. I think you will find the letter key cycle is every 4 years. Pete

[Peter L.]

Re: numbers for spare tire lock

Denny - As Jack pointed out, you will need to find either an original Corvette spare tire lock used in PRODUCTION in either 1967, 1971, 1975, or 1979 since the "B" keyway lock cylinder was used originally in the PRODUCTION spare tire lock.

Also, Joe is correct that any newer SERVICE spare tire locks can be rekeyed to match your glovebox lock key, but unless the spare tier lock cylinder keyway is a "B" the procedure typically involves modifying the lock cylinder keyway so any GM "letter''or even the non-letter key can enter the lock cylinder and therefore any "letter" or non-letter key with the correct key cut can operate the lock. So you will probably want to avoid trying to rekey a non-B keyway spare tire lock if you are striving for originality.

The specific "letter" key keyways used on cars are specific to the PRODUCTION year on a 4 year cycle and are B, D, H, and K. Judges are supposed to check and see if the keyway has been modified by trying to insert the ignition key that would be an A, C, E, or J "letter" ignition key for the 67 and later car in the spare tire lock. If the ignition key goes in to the spare tire lock keyway, it should be a deduction and if you are doing a PV, it will result in a failure. Typically, the spare tire locks available recently thru Chevrolet Parts Service have had the H or K keyways.

Another thing to check for 1967 is that the spare tire lock case is embossed B1 on the bottom. Many later PRODUCTION and SERVICE spare tire locks have B2 embossed on the bottom and the shape of the B2 lock case is slightly different although it will function fine.

Pete