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The Tucker 48 (named after it's model year) was an advanced automobile conceived by Preston Tucker and briefly produced in Chicago in 1948.  This article is not intended to be a complete story about either the car or it's namesake, but rather just to present some of the facts about this car.

Everything you ever wanted to know about the Tucker 48 can best be found by visiting the website for the Tucker Automobile Club of America.  Detailed information about each of the 51 cars can be found at the following link "See a Tucker", after you reach this link, you need only click on any one of the car photo’s shown to gain detailed information about that particular car.
Only 51 (prototypes) cars were made before the company folded on March 3, 1949.  These include the first car (#1000) called the Tin Goose.  Tucker #1051 was not completed at the Tucker factory, so it is not technically considered one of the original 51 cars (Tin Goose + 50).  The car was purchased at the Tucker auction in an incomplete state, and was finished in the late 1980's using leftover Tucker parts.  Forty seven (47) cars survive.  The last thirteen cars did not have engines or transmission when they were auctioned.
The company failure was due to negative publicity initiated by the news media, a Securities and Exchange Commission investigation, and a heavily publicized stock fraud trial, in which allegations were proven baseless in court with a full acquittal.

The Car’s Design:
The initial car design was started by George S. Lawson in the summer of 1944.  Lawson worked on the project for over a year-and-a-half before his design debuted publicly, about February 1946.  Lawson was named the Tucker Corporation's "chief stylist" in February 1946, immediately upon the Corporation's formation.  In December 1946, Lawson resigned from the Corporation after a disagreement with Preston Tucker.  It was only then that Alex Tremulis was hired and further developed Lawson’s design. Tucker.  Initially, Tremulis had a three-month contract, Tremulis' efforts during this phase of design development was featured in a full page advertisement run in numerous national newspapers in March 1947. Tremulis' design was based directly upon the work of George Lawson, but incorporated his own artistic flair.  Next, Preston Tucker hired a team of five designers (Read Viemeister, Budd Steinhilber, Tucker Madawick, Hal Bergstrom and Phillip Egan) from J. Gordon Lippincott, who updated Tremulis' design just as Tremulis had done with Lawson's.  After a month's absence, Tremulis was rehired and the two independent design groups developed full-size clay models side by side in direct competition.  Surviving photographs of the two models reveal that Tremulis' clay design remained unchanged from his March 1947 advertisement proposal and was not chosen for production. The passenger side of the Lippincott team's clay model (they submitted two designs), which incorporated the side profile developed by Tremulis prior to their arrival, was chosen virtually intact for the production automobile's styling.  Tremulis, like George Lawson, was eventually named the Tucker Corporation's "chief stylist".

The Car’s Engine:
The initial engine was a 589 cu. in. flat-6 cylinder with hemispherical combustion chambers, fuel injection, and overhead valves operated by oil pressure rather than a camshaft.  An oil pressure distributor was mounted inline with the ignition distributor and delivered appropriately timed direct oil pressure to open each valve at the proper interval.  Designed to idle at 100 rpm and cruise at 250-1200 rpm through the use of direct drive torque converters on each driving wheel instead of a transmission.  This engine did not work out.  The large 589 cu in engine functioned, but the valve train proved problematic and the engine only produced approximately 88 hp.  The high oil pressure required a 24 volt electrical system and long cranking times at start-up.  Having wasted nearly one year trying to make the 589 work, they started looking for alternatives.  The 589 engine was installed only in the first prototype. (SN 1000) aka “The Tin Goose”.

(The Tucker 589 Engine)

The Franklin 0-355 Engine                                                                                                           The Franklin 0-355 Engine
with Modified Cord Y1                                                                                                                  with a Tuckermatic

The alternative engine was a Franklin air-cooled flat-6 engine, the O-335 made by Air Cooled Motors (and originally intended for the Bell 47 helicopter).  This 334 cu in, 166 hp Franklin engine was heavily modified by Tucker engineers, including a switch to water cooling (a decision that puzzled everyone since).  Thus, very few parts of the original Franklin engine were retained, in the final Tucker engine design. This durable modification of the engine was tested at maximum power for 150 hours, the equivalent of 18,000 miles, at full throttle.

The car’s transmission:
With the 589 and its torque converters discarded, the Tucker 48 now needed a transmission to mate with the Franklin O-335.  The Cord 810/812 4-speed electro-vacuum manual transmissions fit the bill and were used initially. This transmission could not handle the power and torque of the O-335 engine, shearing off gear teeth, if gunned off the line. Thus, the Cord 810/812 design was modified by installing stronger gears and lengthening the case, and named the Tucker Y-1.  It was installed in most Tucker 48‘s. The initial Cord and Tucker Y-1 both used a Bendix electric vacuum shift mechanism, with no mechanical linkage to the steering column shift lever. Problems with electrical connections and vacuum leaks,  hindered shifting, so a new design was sough.
A Borg-Warner 3-speed automatic was tested and was installed on car #1048, but ultimately they wanted to design their own transmission, so Warren Rice, creator of the Buick Dynaflow transmission, was consulted.  A unique continuously variable automatic transmission called the "Tuckermatic" was designed, strong enough to handle the Franklin O-335's power and torque.  A simple but effective design with double torque converters and only 27 parts.  The double torque converters allowed a continuously variable drive ratio, with only one forward gear and one reverse gear, which used the torque converters to vary the transmission ratio based on load and engine speed.  This design, only made it into two of the car’s, #1026 and #1042.  Because the two torque converters on the Tuckermatic made the engine/transmission unit longer, the fuel tank in the Tucker '48 had to be moved from behind the rear seat to in front of the dashboard for all Tuckers from car #1026 forward, even though only two of them actually had the Tuckermatic installed. This also had the added advantage of improving weight distribution on the car.
Rather than springs, Tucker 48’s used an elastomeric (rubber) 4-wheel independent suspension.  The rubber elastomers were developed with assistance from the Firestone Tire Company and used a special Vulcanization process to produce a specific spring rate.  On cars #1001 and 1002 the rear wheels could not be removed due to the stiffness of the suspension and the rear wheel arch fender design.  On cars #1003 & up the rear fender shape was changed so the tire could be removed easily.  Aside from the fender changes, the rear suspension remained the same.  The front suspension was installed in 3 versions, cars #1001–1002 used a rubber torsion tube design which suffered from severe toe-in during heavy braking. On cars #1003–1025, a rubber sandwich-type suspension (with a rubber block sandwiched between upper and lower A-arms) was used, however this type was severely stiff.  On cars #1026 & up a suspension design using a modified version of the original rubber torsion tube, with the toe-in braking problem corrected, was used.
The front bumper of the car was lengthened on car #1003 & up to prevent the center headlight from being the forward most point on the car.  The lengthened bumper protected the center headlight from being crushed if the car were pulled too close to a wall or barrier.
Original Six Tucker 48 Paint Color Codes:
100: Black
200: Waltz Blue
300: Green
400: Beige
500: Grey (Silver)
600: Maroon
Original Three Tucker Interior Trim Color Codes:
900: Light green
910: Light Blue
920: Light Beige
Original design features which were never achieved were:
Magnesium wheels
Self-sealing tubeless tires
Disk Brakes
Fuel Injection
Direct-drive torque converter transmission 
A directional third headlight (the one installed does not track).
Innovations which did make the car were:
Rear-engine and rear wheel drive
Perimeter frame for crash protection
Roll bar integrated into the roof
Steering box behind the front axle, protect the driver in a front-end accident
Instrument panel and all controls within easy reach of the steering wheel
Dash padded for safety
Windshield made of shatterproof glass and designed to pop out in a collision
Parking brake had a separate key lock to prevent theft
Doors extended into the roof, to ease entry and exit
Sources:  WikiPedia - Tucker Automobile Club of America