In 1942, Ford built a handful of Lincoln and Mercury models with a new type of automatic transmission called Liquamatic—then quickly withdrew it from the market. This is the story of that brief and spectacular failure. 

It’s true. Ford actually offered an automatic transmission in 1942 as an extra-cost option on Mercury and Lincoln models. But the development is virtually unknown today, in large part because the company withdrew it from the market almost as quickly as it was introduced, and all the units were ordered shipped back to the factory. Here’s the story of an automatic transmission that almost never was.

Thanks to the Early Ford V-8 Foundation Museum in Auburn, Indiana (shout out to curator Josh Conrad) there’s an example of the incredibly rare Mercury Liquamatic on public display, as shown here. Liquamatic was essentially a conventional three-speed manual transmission and foot-operated clutch, but with several important additions. First, a hydraulic fluid coupling was mounted on the flywheel in front of the clutch assembly, which provided clutchless starts, stops, and shifting. Next, an additional shift lever was incorporated on the right side of the gearbox, which enabled a vacuum-operated, electrically controlled servo mechanism to shift the gearbox from second to third gear and back again.

So with Liquamatic, drivers could clutch and shift manually through first, second, and third gears, or leave the shift lever in third and allow the transmission to operate automatically with clutchless starts in second gear. Obviously, with the slippage of the fluid coupling combined with second-gear starts, performance in automatic mode would be leisurely, to say the least.

This schematic view of the Lincoln version of Liquamatic provides more explanation. At 12 mph, a servo powered by the engine’s manifold vacuum (controlled by an electric governor switch and solenoid) performs the automated shift from second to third gear. There was also a throttle-operated kickdown switch to downshift the transmission from third to second gear at speeds below 35 mph.

Lincoln’s Liquamatic transmission also included a conventional overdrive unit, as shown above, which engaged at 23 mph or above in any forward gear, or which could be overruled by a lockout switch on the instrument panel. While this drawing (from the 1946 MoTor’s Repair Manual) refers to a 1941-42 Liquamatic transmission, it appears the extra-cost option—a rather costly one at $189—was offered in 1942 only. The supplier of both units was Detroit Gear, a division of Borg-Warner.

With its special cylinder block casting required to make room for the fluid coupling in the Ford V8’s integral bell housing, the Liquamatic drivetrain unit was four inches longer than the conventional three-speed manual setup, and the radiator was relocated accordingly. Reportedly, only 744 of the approximately 23,000 cars produced by Mercury in 1942 were equipped with Liquamatic, and some sources say a mere eight Lincolns were so equipped.

For reasons not completely known to us—though we’re guessing poor performance was one factor—Liquamatic was withdrawn from the market almost as quickly as it appeared. Whatever the problems, they were serious enough that dealers were instructed to retrofit all customer cars with conventional manual transmissions immediately. Meanwhile, the Liquamatic engines and transmissions were to be crated up and shipped back to the factory. However, one Mercury dealer in Minnesota never got around to shipping its Liquamatic unit back to Dearborn, and it was discovered there, still in its crate in the parts department, in 1971. It’s the very same one on display at the Early Ford V-8 Museum, and experts believe it may be the only complete Mercury Liquamatic unit in existence. The Ford Motor Company wouldn’t offer its own automatic transmission again until 1951.