GM Steering Column Compatibility, Interchange & Repair Guide
It is one of the first interior modifications thought of on a new build; upgrading the steering column to a tilt unit offers the driver more room and flexibility in a seating position for comfort and performance. Installing a tilt steering column allows you to adjust the steering wheel position to best suit your body type, seating position, and driving style, especially on older vehicles without power steering. Manual steering cars have large steering wheels. If you have been in a C1 Corvette, then you know exactly what we mean—the steering wheel is a gigantic 17” diameter with a static column, making ingress and egress from the vehicle difficult if you are a svelte person. Put on a few extra pounds, and it can be nearly impossible, not to mention actually driving with that giant wheel rubbing your legs. A tilt column can make all the difference in the world for the actual usability of the vehicle, not just boosting the features of your car.
Invented in the early 1900s, tilt columns were very rare in production vehicles until the 1960s, when Cadillac began using them in a few high-end models. It wasn’t until 1967 that the Saginaw 7-position tilt steering column could be found on almost every model order sheet. Designed in 1963, the Saginaw 7-position tilt unit is the basis for every other GM column to come after. While nearly every steering column used today is a hinged design, the tilting head design remains the most popular design for aftermarket installations. Because it was used for so long and in so many models, GM steering column compatibility covers most GM cars, even back into the 40s, which some caveats, of course. The steering column is your connection to the road and the final component in a complex arrangement of components that make up the vehicle’s steering system.
GM Steering Column Identification
Prior to the mid-60s, many vehicles still used steering columns that were solid-shaft designs, where the column shaft was integral to the steering gearbox, which is a serious safety issue in a front-end collision. This led to the US Federal requirement that all vehicles built in 1968 and up must have collapsible steering columns. In order to do this, the columns became divorced from the gearbox itself. For GM, the Corvette lost its single-shaft column with the C2 design in 1963, and all C1s have the single-piece column. The advent of the collapsible column hit GM in about 1967 when most of the lineup had collapsible column shafts. The column has two shafts inside the column, one inside the other. This is typically about 18 or so inches of column length, and there is a plastic pin that holds the two pieces together. The shafts are shaped in a “double-D” configuration, so the two shafts can’t rotate on each other. In the event of a head-on collision, the pin holding the shafts together sheers, allowing the inner shaft to slide up, eliminating the transfer of energy to the column towards the driver. GM steering column compatibility with older solid-shaft vehicles requires converting to a divorced gearbox, which is available for most GM vehicles.
The 1960s saw a lot of development in this area. In the early 60s, most GM vehicles had integral steering shafts, including the first gen Chevy II (62-66). However, by 1964, most new body styles featured divorced steering column designs where the column is one piece that bolts to the steering box via a rag joint. These columns were still quite long and did not have collapsible shafts, so even though the column could break away from the gearbox, it was still dangerous. The push to use collapsible shafts brought on another change at GM—the 3-piece steering system where the gearbox connected to a collapsible intermediate shaft which then connected to a shorter steering column at the firewall. This is the column design that has lasted ever since, as all modern vehicles use a version of this design. While the design was predominately one of safety, the end result is the 1968-1994 GM truck steering column design that is most commonly desired.
After 1995 (and some prior to), GM steering columns got big. The headstock is ballooned in diameter with large plastic covers designed to hide all the new required features, such as airbags and vehicle interlock security systems. The columns are unsightly for anything other than the original vehicle, so they rarely are swapped into older vehicles. The premium design for stock tilt columns is from 1968-92 before GM started using plastic column covers; these columns are all steel, which is easier to modify. This is the design that the entire aftermarket steering column industry is based on and for good reason. They look good, function well, and are easy to service. That isn’t to say that any old tilt column will fit your needs, GM steering column interchange is replete with multiple options that you need to look for when shopping for a take-out column.
Shift/non-shift
The most significant factor for GM steering column compatibility is whether or not you want to shift the column or not. If you have a manual or floor shifter, then non-shifted is the obvious choice. This can be tricky though, as non-shift original GM columns are getting hard to find, and they are relatively pricey. Most of the vehicles these were installed in from the factory had both auto and manual configurations, so it is a crapshoot. Premium models of common body styles in the late 1960s and 70s, such as Chevelle, Gran Sport, GTO, 442, etc., had floor shifters for the autos, so their columns were all non-shift while their base counterparts (Malibu, Skylark, Le Mans, Cutlass, etc.) typically had column shifted automatics when optioned with an auto transmission. GM actually offered manual-shifted columns (3-on-the-tree) through 1985, so there are all kinds of oddball options out there if you look hard enough.
Key/non-keyed
This one is not as big of a deal for most swappers, but it could be depending on your vehicle. Most GM vehicles from the mid-60s on up had keyed columns. There are exceptions; 63-67 Corvettes, 73-81 Chevy/GMC vans (shifted), and 60-72 C10s (70 was the first year for tilt in C10s) all have non-keyed columns.
GM Steering Column Lengths
One of the hardest things to pin down is the length of the factory columns, and there are a lot of very unique rare-model columns and options that can change the length of the columns from year to year. GM steering column interchange requires that you know the space between the steering column and the gearbox itself. If you are working with a non-GM vehicle and not just swapping a tilt unit from the same model, you need to consider the intermediate shaft length and the distance from the column bell to the firewall, as these are critical dimensions for swapping a GM Saginaw tilt steering column. The following is a list of common lengths for specific year-range models. This list represents the most common GM tilt steering columns.
Common GM Steering Column Lengths
- 69-72 C10 Truck: 35” long, 3/4-36 spline end, no key, some are shifted
- 72-84 C10 Truck (Early): 3/4-36 spline intermediate shaft, no wiper/high-beam switch
- 85-94 C10 Truck (Late): 1” DD intermediate shaft, has wiper/high-beam switch and cruise control options
- 73-89 GM Van: 34” long, all years are shifted, w/o key
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- 73-83 Van has 3/4-36 spline
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- 84-89 Van has 1” DD shaft with wiper/cruise control
- 70-81 F-Body Camaro/Firebird: 34.62” long, pre-78 have 3/4-36 splines, later units have 1” DD coupler
- 82-92 F-Body Camaro/Firebird: 33.5" long, 1” DD shaft, with wiper/cruise controls
- 68-72 A-Body: 31.25” long, 3/4-36 spline
- 73-77 A-Body: 35.5” long, 3/4-36 spline, rare models have cruise controls
- 78-87 G-Body: 32.5" long, 1” DD shaft, with wiper/cruise controls
- 71-76 B-Body: 35.5” long, 3/4-36 spline
- 77-90 B-Body: 33.75” long, 1” DD shaft, with wiper/cruise controls
- C3 Corvette (68-82)
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- 68-76 Corvette: 38.3” long, 3/4-36 spline
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- 78-82 Corvette: 36.3” long, 1” DD shaft, 81-82 columns have cruise controls on column
- C4 Corvette (84-96): 32.5" long, 1” DD shaft, with wiper/cruise controls
GM Steering Column Compatibility
There are two styles of mounting for factory columns- welded flange or slip compression mount. Most GM columns use welded flanges on the interior tube under the dash, typically about halfway down the shaft after the bell. Corvettes and some trucks use 2-bolt flanges, and most passenger cars use 3-bolt flanges. Unless you are working with a GM vehicle, the flanges most likely will not line up with anything your vehicle has, so you can either cut the flange off and use a universal column mount, column drop, weld up a new flange plate, or make an adapter to use the factory flange in your vehicle. The option you choose depends on the vehicle and your skill level. Keep in mind that steering integrity is one of the two most important aspects of any vehicle. If you lose steering control because your column comes loose, you have a very real problem.
Wiring
There are two main column wiring types for tilt columns—68-76, which uses a 3-7/8” wiring connector, and the 1969-96 4-1/4” connector. The longer connector was only used on two models in 69—Corvettes and B-body cars. The rest of the models used the shorter plug until 1977 when all models switched to the long style. More can be found in our Steering Column Wiring Guide.
Common problems
All steering columns can have issues with ignition components; however, the main issue with GM tilt columns is the tilt head unit. Years of being used as a grab handle to get in and out of the vehicle put a lot of strain on the tilt mechanism, which is the primary concern. The latch that holds the head in place can break, the pivot pins wear out (the leading cause of loose tilt heads), the high-beam switch rod mechanism can break, and the ignition switch can break. A GM tilt steering column rebuild is not terribly difficult, but it does require patience and a specialty tool for pivot pins. A C10 steering column rebuild is often required when using truck columns, as the wheel is the main grab handle most drivers use when climbing into the old truck.
Measuring
There are several common measurements you need for a steering column. The main ones are the overall length which is measured from the end of the shaft (engine side) to the end of the column bell, where the steering meets the column, NOT including the section of shaft that the wheel mounts on. This is a common misconception that causes issues for swappers. The other vital measurements are end shaft connection, which for GM columns is either 3/4”-36 spline or 1”-DD. You also need to know the gearbox input shaft type, which is typically a 3/4"-36 spline. 3/4" DD, 17mm-DD (most rack and pinions), or 1"-DD. There are some 1”-48, but that steering box is relatively uncommon.
Other required measurements are the length of the bell flare to the shaft end (engine side), which is the length of the shaft that is under the dash after the column flares to the bell. This varies wildly by year and option (column-shifted units are typically 2 inches longer than non-shifted units).
You can find more on measurements in our Speedway Motors Steering Columns Tech Talk.
Swapping a GM Saginaw steering column is simple for most vehicles, even if you have to make your own intermediate shaft. Buying used can save you money if you are willing to do some GM tilt steering column repair. There are online sellers of rebuilt units as well, which will cost you a fair bit more than even a new aftermarket column. If you do decide to rebuild, it is a good idea to buy a GM steering column repair manual, which will make the process easier, especially if you go completely through it. You can also eliminate these mitigating factors by opting for a new aftermarket column.
Sources
Wayne Wiles GM TILT Steering Column Sales and Service 260-450-3158
Ididit 610 S. Maumee St. Tecumseh, MI 49286 517-424-0577