The designation’s so widespread, it’s almost become gospel among Mustang enthusiasts and the collector car world in general. You’ll see 1964-1/2 as a model year in the titles of Mustang books, in prior Hemmings articles (nostra culpa), even on Ford’s own website. Except, officially, Ford never designated any Mustang as a 1964-1/2 model year car.
“All of the first production Mustangs built from February 10, 1964, through July 31, 1964, were titled as 1965 model year cars,” according to Robert Fria, an expert in pre-production and early production Mustangs who wrote the definitive book on the subject, “Mustang Genesis: The Creation of the Pony Car.” As Fria and many others have pointed out, just looking at the VIN of any early production Mustang should bear that out: All of them – whether the one Fria discovered with serial number 100002 or the one that Captain Stanley Tucker bought with serial number 100001 – start with the digit 5 for the 1965 model year.
Case closed, really short article, right? So then why did the 1964-1/2 “model year” become so widespread to the point where it gets its own entry in year-by-year Mustang reference books and where the Mustang Club of America reportedly considers 1964-1/2 as a separate model year?
Part of it comes down to the introduction of the Mustang in April 1964, well out of line with the traditional model year cycle: The rest of the 1965 Fords didn’t debut until that September. While unusual in comparison with prevailing trends through the rest of the industry, it was actually in line with Ford’s mid-year introductions of the Falcon Futura and Galaxy 500XL Sports Hardtop the year prior, as Brad Bowling pointed out in the “Standard Catalog of Mustang” (which, incidentally, has an entire section on the “1964-1/2” Mustang). Indeed, given the success of such introductions – the Mustang essentially had the field to itself when it came to new-car publicity that spring, and that introduction date may have even been key to the avalanche of first-year sales – one has to wonder why we haven’t seen many subsequent mid-year introductions. (Outside of unintentional ones like the 1970-1/2 Camaro, its introduction delayed by a strike.)
Speaking of sales, Ford reported a total of 680,989 first-year Mustang sales, though that total is comprised of the 121,538 early Mustangs sold prior to the traditional start of the 1965 model year and the 559,451 sold during the 1965 model year.
Part of it also arises from the many changes that Ford introduced to the Mustang around the start of traditional 1965 model year production, leading enthusiasts to start referring to the early Mustangs as “1964-1/2” cars simply to differentiate them from the regular production year cars. Those early cars, for instance, had a much different engine lineup, consisting of the U-code 101hp one-barrel 170-cu.in. six-cylinder, the F-code 164hp two-barrel 260-cu.in. V-8, the D-code 210hp four-barrel 289-cu.in. V-8, and the famed K-code 271hp four-barrel 289-cu.in. V-8. Once regular 1965 model year production started, only the K-code remained; the T-code 120hp 200-cu.in. six-cylinder replaced the U-code, the C-code 200hp two-barrel 289-cu.in. V-8 replaced the F-code, and the A-code 225hp four-barrel 289-cu.in. V-8 replaced the D-code. In addition, all early 1965 Mustangs had generators while all regular production year 1965 Mustangs came equipped with alternators.
Mustang enthusiasts generally use engine codes and the presence of a generator to distinguish early from regular production 1965 cars, but a host of other changes took place in late summer 1964. Bowling notes a number of those changes, including the switch from C-clips for the interior door handles to Allen screws, slightly wider Mustang nameplates, and the switch from interior-color to chrome door lock buttons. Others have noted that regular production model year cars had an adjustable front passenger seat in place of the earlier fixed seat, that the early cars equipped with automatic transmissions had smaller shifter handles, and that the fuel-filler cap was given a tether to make it more theft-resistant. By far the most comprehensive accounting of the changes appears to be in Colin Date’s book, “Original Mustang, 1964-1/2 – 1966,” in which he points out, for instance, slight sheetmetal changes at the base of the windshield wipers, the switch from rubber to plastic trunk mats, color-keyed seat belt latches replacing chromed latches, different AM radios, and the brake light switch location moving off of the master cylinder. Even paint colors and codes changed quite a bit from early to regular production 1965 cars.