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1967-1971 Ford Thunderbird


1967 Ford Thunderbird and Unit-Body Construction

Forward-looking auto designers recognized the inherent and inevitable logic of giving the 1967 Ford Thunderbird unit-body construction. Nash and Hudson had already proven its viability, and Chrysler launched a massive effort to unitize most of its product line for 1960.

1967 Ford Thunderbird
The unit-body assembly that served Thunderbird
since 1958 was discarded for body-on-frame in 1967.

At Ford, body engineering director Henry Grebe believed that all Fords, Mercurys, and Lincolns would eventually convert to an integral body/frame. Not everyone in Dearborn agreed, however, and the company approached the unit body cautiously, converting one or two products at a time. Naturally, they began with the cars they thought could benefit most from the change.

Unit construction made sense for the first four-seat Thunderbird in 1958, allowing it to squeeze more interior room into a lower profile. Lincoln also switched over to unit construction for 1958, hoping that a technological edge over Cadillac might boost languishing sales.

Ford opened a new plant in Wixom, Michigan, as the exclusive assembly point for Thunderbirds and Lincolns, which shared cowls, windshields, and some other body hardware.

A unit body made sense for a small car as well, and so the compact Falcon of 1960 and mid-size Fairlane of 1962 were Ford's next two unitized products. But for the vitally important full-size line, Ford management hedged and ordered a conventionally constructed car to be developed in parallel with a unit-body version.

According to engineer Jim Wagner, these programs were well under way when the 1961 Pontiac appeared, with its relatively rigid body "nodal-point mounted" on a somewhat flexible perimeter frame. The Pontiac design promised unit-body strength with near-ideal sound isolation, so Ford enthusiastically adopted this best-of-both-worlds approach for the all-new 1965 full-size Ford and Mercury.

One could almost think of the 1965 Ford as a unitized (Ford used the term "rigidized") body with a full-length subframe to isolate the suspension and driveline. All 14 body mounts were located either in front of or behind the passenger compartment, which helped minimize noise, vibration, and harshness.

A famous advertisement claimed that the 1965 LTD rode more quietly than a Rolls-Royce Silver Shadow. That wasn't quite true: Tests had proven the Ford to be significantly more quiet, but the ad agency feared that no one would believe that and fudged the results to narrow the gap between the two cars.

"Given that success, it was a foregone conclusion that the company's large cars would follow the same course in the future," explained Wagner. Similar construction was applied to the Thunderbird for 1967, the Continental in 1970, and even the Torino in 1972.

See the next page to follow the Ford Thunderbird story into 1968-1969.

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