Will a steering column from a 67 work in a 66? Is it the same coupler?

The 1967 column was the first GM energy absorbing "safety" steering column. All steering columns before 1967 were rigid designs. These old rigid designs could be quite dangerous since the solid steering shaft could be pushed rearward into the driver in a severe frontal collision.

The first generation energy absorbing column had a metal tube that extended down through the instrument panel and down to the floor. This tube had strategic metal cutouts to allow the column to crush and absorb energy (the steering shaft was also designed in two pieces to allow it to collapse as well). Unfortunately, the metal cutouts made the column very "limp" in bending. This required GM to design a very large (and complicated) mounting bracket under the dash to regain some bending stability.

To cobble a 1967-68 column into a 1966 vehicle would require major structure additions to the instrument panel and dash to stabilize the column.

The 1969 and later columns were redesigned and were much stiffer. However, now you have the problem that all of these second generation steering columns have the ignition lock cylinder protruding out of the steering column head.

Thanks for the information.

Could the 69 & newer column be fitted with the 66 upper head parts?

Anything is possible. But, things weren't even designed similar. There isn't any chance that they will just bolt together. It would take a lot of cobbling and you would have to machine adapters for the 1966 upper end parts.

Your 1966 Chevelle had a OEM rigid steering column. Why don't you purchase a Flaming River or Idit aftermarket steering column to replace your original?

I think that they have some models designed specifically for your 1966.

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