Where Can I Find A 3 Speed Transmission For A 1972 GTO?

Greg Zyla
Q: Greg, could you please tell me if the M13 Trans listed on my 1972 GTO build sheet (enclosed) is indeed the 3-speed manual that you talked of in a recent Auto Roundup Car Collector Corner column?
If so, where can I purchase one as I would like to get my GTO to its original condition and shape. You do a great job writing your articles. Thanks, L.C. Honeycutt, Dunn, NC.
A: L.C., thanks for the nice words. The transmission listed on the build sheet you sent me is indeed the Heavy Duty 3-speed transmission I spoke of in the a recent Auto Roundup/Car Collector Corner column (Vol 7, No. 694, Page 35).
This Heavy Duty 3-speed, depending on year, is called either a Dearborn (1965-1969) or a Muncie (1970-1973) M13 unit, and utilizes the code M13 on the sheets.
Surprisingly, a 3-speed transmission was the standard transmission for all GTO's from 1964 through 1972, although in its initial year of 1964, the 3-speed was an M12 unit made by Muncie, but after March of 1965, GTO switched to the stronger M13 Dearborn (Ford style) unit.
In 1974, the last year of initial GTO production, an M11 made by Saginaw became the standard 3-speed, replacing the Muncie M13 that came in GTO's from 1970 to 1973 (both Dearborn and Muncie were similar).
Four speeds were available in GTO's, notably the Muncie M20 wide ratio, M21 close ratio and M22 rock crusher, and automatic fans had either a two-speed Powerglide from 1964 through 1966 or, from 1967 on, the three-speed Turbo-Hydramantic M40 option, which would become known as the "Turbo 400."
As for M13 availability, my best advice is to check eBay Motors regularly, or pick up Hemmings Motor News and Auto Round-Up magazines for tracking down your original Muncie M13 3-speed.
You may want to consider an ad in either of the two publications I mention under "Parts Wanted," and I feel confident you'll find your M13. If you want to talk to an expert, contact D&L Transmission at 1-631-351-4837 and they may be able to help quickly.
D&L is located in Long Island, NY, and known as specialists for GTO Transmissions and all hard to find Muncie and Saginaw units.
Thanks for your letter and excellent copy of your GTO build sheet. Good luck!

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