Through the mid-1960s, General Motors divisions basically used two styles of the same in-dash ignition lock. For simplicity, I remember them as the concave and the “cowboy hat” models. For most applications they were interchangeable. Both styles of ignition locks were manufactured by Briggs & Stratton (B & S). B & S locks, components and key blanks were available through locksmith distributors. Most parts were in stock and available for pickup at Will Call. However, many locksmiths would keep several ignition locks in their service vehicle and shop stock.

Fast forward through the 1980s, 1990s and into the new millennium. General Motors divisions were changing ignition lock models at a rapid rate. A number of the manual and automatic transmission equipped vehicles used different ignition locks. Some of the divisions were using a basic lock design; however, their model was not interchangeable with other divisions. Anti-theft devices had been VATS and PK3/MRD were being introduced.

STRATTEC, the automotive lock division spin-off from Briggs & Stratton, was no longer the only lock supplier to GM North America. Overseas lock manufacturers (Ortec/Huf/etc.) had begun to produce locks and related components for a growing number vehicle/ignition lock models. I lost count at 38 different General Motors ignition locks somewhere in the late 1990s.

At that time we would keep the STRATTEC (B & S) “big red book” and the annual Automotive Lock & Key Catalogs available to check if the ignition/door/deck lock(s) that needed replacement or servicing was available through STRATTEC. If not, and if ASP did not have locks or servicing components, pricing would be very, very different as most lock and replacement components were and are expensive from the dealership. And even worse, most of the parts had to be ordered and would require at best one to two days and at worst, a week or more. Many customers did not like to pay the two service calls. The first service call was to diagnose the problem and order the necessary parts. The second call came when the dealership had the parts and included pickup and repair or replacement.

Let’s continue to 2008. Ortec has left the North American lock market, leaving STRATTEC to be the supplier of most of its automotive locks. Other changes are occurring within the General Motors lock supplier situation. According to a source at STRATTEC, they are now just about back up to supplying 90 percent of the North American General Motors vehicle locks. This includes new vehicles and existing vehicles. This means fewer locks and components have to be purchased and waited for from the division dealerships.

During the last couple of years, STRATTEC has begun introducing replacements for non-STRATTEC ignition and door locks. This has made the lives of automotive locksmiths easier and has eliminated the need to purchase expensive tools, tumblers and springs in order to service an ignition lock.

For this article, I will list only the different General Motors vehicles/ignition locks that are not originally produced by STRATTEC with the STRATTEC replacement ignition locks and applicable years. I will also include the STRATTEC ignition lock and key blank part numbers, the key code series and the keyway.

Please note: This list is a work in progress, as we have not been able to examine every model vehicle with every manufacturer’s key blank. We apologize for any error or omissions to this list.
The following keying information is applicable when servicing General Motors vehicles equipped with ten-cut locks. General Motors has introduced a number of different code series for ten-cut lock mechanisms. They include Huf, Ortec, STRATTEC, etc. They include the 75 and 93 groove locks. Shown in Chart 2.

There are several important points to be aware of when servicing GM vehicles having the above code series. Probably, the most important is variations within the O5000-O6999 code series.

The ten-cut lock spacing is bow to tip, with the key blade gauged from the tip stop:
1. - 1.034”      
2. - .942”        
3. - .850”        
4. - .757”        
5. - .665”        
6. - .573”        
7. - .481”        
8. - .389”        
9. - .297”        
10. - .205”

When the O5000-O6999 code series is used with 75 groove keyway locks, use the following depths of cut:
1- .315”          
2- .290”          
3- .265”          
4- .240”

Use HPC card CX215 or the Ilco card 567 for 75 groove keys.
When the O5000-O6999 code series is used with 93 groove keyway locks, use the following four depths of cut:
1- .325”           2- .305”           3- .285”           4- .265”

Use HPC card CX263 or the Ilco card 2020 for 93 groove keys.

When the O5000-O6999 began using the 93 groove key, they changed the depth dimensions using the dimensions from the G0001-G3631 code series spaces and depths. The reason was that a #4 depth in the 75 groove is much deeper (less blade remaining) than a #4 depth in the 93 groove.

For more information on automotive locks discussed in this article, contact your local locksmith distributor or STRATTEC Security Corp. at: 877-251-8798 or