I Like Ike’s Brakes: Exploring Mamie Eisenhower’s Chrysler Limousine

Riding on its 145-inch wheelbase, the 25-foot long Mamie Eisenhower Crown Imperial limo is truly massive.
Riding on its 145-inch wheelbase, the 25-foot long Mamie Eisenhower Crown Imperial limo is truly massive.

What does it take to stop a four-ton limousine carrying the leader of the free world? If you answered “great brakes,” then you’ll appreciate the story of how I recently stumbled onto a vintage Chrysler Imperial of double-whammy historical significance. Back in January of 1953, Dwight D. Eisenhower was sworn into office as the 34th President of the United States. Though a fully modified 1950 Lincoln Cosmopolitan limousine was already at his disposal for parade use (a legacy from the previous Truman administration), it’s a fact that Ike was a fan of Chrysler automobiles and owned several in his private life, including 1948, 1950 and 1952 models.

It is unclear whether he personally requested them or not, but in early 1953 Chrysler leased a pair of nearly identical black Crown Imperial limousines to the White House motor pool. One was intended for the President, the other for his elegant wife Mamie, and that car is on display here. Each limo was initially constructed by Chrysler before being sent to Philadelphia-based Derham coachworks for bulletproofing and the addition of customized radio and air-conditioning equipment.

Winter chill frosts the Derham-installed bulletproof glass. The chrome vents are part of the elaborate trunk-mounted air conditioning system.
Winter chill frosts the Derham-installed bulletproof glass. The chrome vents are part of the elaborate trunk-mounted air conditioning system.

Like all presidential ground transportation, chauffeurs were (and continue to be) the norm. Dignitaries rode in the plush comfort of the cabin, free to concern themselves with world affairs and matters more pressing than the operation of the car itself. About those chauffeurs, when they stepped on the brake pedal of these special 1953 Chrysler limousines, each was met by a unique experience. Unlike the conventional drum-and-shoe type brakes fitted to other limos in the White House fleet since the earliest Stanley Steamers of the Theodore Roosevelt administration (1901-1909), these Chrysler vehicles were equipped with Ausco-Lambert disc brakes at all four wheels.

Derham fortified the floor pan with blast shielding for extra security. Crown Imperial limos used a specific rear axle with a 69-inch track width. A foot wider than the front tire track, the added room made way for the plush, couch-like back seat. The chassis rust is consistent with the level of corrosion seen throughout the car. Still, a dedicated restoration team could easily make it all like new.
Derham fortified the floor pan with blast shielding for extra security. Crown Imperial limos used a specific rear axle with a 69-inch track width. A foot wider than the front tire track, the added room made way for the plush, couch-like back seat. The chassis rust is consistent with the level of corrosion seen throughout the car. Still, a dedicated restoration team could easily make it all like new.

Though disc brakes have become commonplace in today’s world, drum brakes were the rule back in the days when Ike was in charge. Drum brakes, as the name implies, incorporate a large circular metal drum with a smooth friction surface machined into the circumference of the inner face. When brakes are applied, a pair of asbestos-lined brake shoes expands outward and makes contact with the spinning drum. The resulting friction is what slows the rotating wheels and brings the car to a stop. Though simple and reliable, drum brakes tend to trap the air heated during braking activity, and overheating can result quickly.

What’s more, the larger and heavier the vehicle to be stopped, the bigger the drums must be in order to keep pace with the job at hand. On a typical American passenger car of the early fifties, wheel rim diameters of 14 and 15 inches restricted the maximum diameter of the brake drums in use. On a typical 1953 family sedan weighing 3,200 pounds or so, chassis engineers could rest assured that adequate braking would be provided by a quartet of 10- or 11-inch brake drums. But when vehicle mass grew to the 5,900 pound empty weight of these bullet-proofed Eisenhower Chrysler limos, something more was needed. Prior to 1949, Chrysler limousines (and full size models alike) relied on 12-inch diameter brake drums — as did the rest of the industry.

With the bullet and soundproof glass partition raised, the chauffeur wasn’t privy to national security discussions — or the comfort of A/C. The floor-mounted Mopar Cool-Air accessory A/C unit gave relief on summer days. The odometer reads 44,590 miles.
With the bullet and soundproof glass partition raised, the chauffeur wasn’t privy to national security discussions — or the comfort of A/C. The floor-mounted Mopar Cool-Air accessory A/C unit gave relief on summer days. The odometer reads 44,590 miles.

But with its industry-leading adoption of standard-issue (no extra cost) hydraulic four-wheel brakes as early as 1924, Chrysler knew there was room for improvement and in 1939 collaborated with the Auto Specialties Manufacturing Company (Ausco) of St. Joseph, MI, to evaluate a new concept in automotive braking. Deviating from the external-contracting and internal-expanding shoe-on-drum systems in use throughout the U.S. auto industry in the day, the new approach used a stationary disc enclosed by a cast-iron housing that rotated with the spinning wheel.

Each face (inner and outer) of the stationary disc was fitted with six friction pads, and the disc itself was split down the middle so each facing could move outward, thus bringing the brake pads into contact with the spinning housing when braking force was desired. The expansion was triggered by twin hydraulic cylinders acting upon lever arms; then extra force was added thanks to an ingenious system of ramps and balls that contributed extra wedging-action between the pads and discs. The end result was a 30-percent increase in surface area versus 12-inch drums and reduced pedal effort required for stopping.

Mold and dust cover the wool broadcloth-covered passenger compartment where Mamie once rode. The partially deployed jump seat is one of two that fold into the partition separating the leather-adorned chauffeur’s compartment. Maximum capacity is seven people, including the driver.
Mold and dust cover the wool broadcloth-covered passenger compartment where Mamie once rode. The partially deployed jump seat is one of two that fold into the partition separating the leather-adorned chauffeur’s compartment. Maximum capacity is seven people, including the driver.

Chrysler torture tests from the day involving the relationship between brake pedal pressure and repeated panic stops are eye opening. While conventional drum brakes required 120 pounds of pedal pressure to lock all four tires, the disc brakes took only 75 pounds to achieve lockup. After five back-to-back panic stops, the drum brakes required 200 pounds of effort and overheated (faded) to the point of being useless. By contrast, the discs were good for 15 panic stops with pedal pressure rising to just 90 pounds by the end of the test session.

The Ausco-Lambert system was very unique and radically different from today’s concept of disc brakes. Today, when we think of disc brakes, we generally think of a shiny, machined rotor that’s connected to the wheel hub and a stationary brake caliper mounted to the spindle. When applied, the caliper pistons clamp the brake pads against the rotor to bring the wheels to a stop. Ausco’s layout was different, and its enclosure of the disc and friction pads within a finned cast-iron housing has led many to incorrectly assume it is a drum-type brake design. One look at the accompanying illustrations will cure that misconception.

Ausco-Lambert disc brakes may look similar to conventional drum brakes, but within the finned cast-iron housing is a stationary double-sided brake disc. Mounted at all four wheels, these brakes were the only safe way to stop a fully laden 7,000-pound Crown Imperial limo. When fitted to lighter Chrysler road cars, stopping power was astonishing. Today, repair and service parts are still available from specialty suppliers.
Ausco-Lambert disc brakes may look similar to conventional drum brakes, but within the finned cast-iron housing is a stationary double-sided brake disc. Mounted at all four wheels, these brakes were the only safe way to stop a fully laden 7,000-pound Crown Imperial limo. When fitted to lighter Chrysler road cars, stopping power was astonishing. Today, repair and service parts are still available from specialty suppliers.

The first Ausco-Lambert disc brake system installed on a Chrysler automobile seems to have been an experimental fitment aboard a 1939 Plymouth. Beyond that, little was heard of the Ausco-Lambert “Safety Brake” system until it popped up — as standard equipment — on all 1949 Chrysler Crown Imperial limousines and as a $400 option on smaller Chryslers — including the highly collectible Town & Country wood- and steel-bodied prestige models. This use of four-wheel disc brakes was yet another industry first for Chrysler. The next domestic automaker to employ disc brakes at all four wheels wouldn’t do so until 1965!

In their day, disc-brake-equipped Chryslers were regarded as the best-stopping American cars on the road and were praised by drivers — and chauffeurs — for their easy pedal effort. Records show that around two thousand 1949–1954 Chryslers were equipped with Ausco-Lambert four-wheel disc brakes before the costly option was dropped for the 1955 model year.

Not often seen on formal Crown Imperial limousines, Mamie’s car rides on 15x8-inch chromed Kelsey-Hayes wire wheels, a $290.25 factory option. Modern photos of Ike’s limo in France depict more typical full-disc wheel covers. It is not known if these wire wheels were factory-issued or added later.
Not often seen on formal Crown Imperial limousines, Mamie’s car rides on 15×8-inch chromed Kelsey-Hayes wire wheels, a $290.25 factory option. Modern photos of Ike’s limo in France depict more typical full-disc wheel covers. It is not known if these wire wheels were factory-issued or added later.

Key factors that enabled Chrysler to return to more conventional (and less expensive) drum brakes on all models in 1955 (including the massive Crown Imperial limo) were the advent of the Chrysler-developed Center-Plane braking system, which used two hydraulic cylinders per drum to force the brake shoes against the drums evenly, and the redesigned 1955 body shell. Unlike the upright body types of 1954 and before, the 1955 models were lower, longer and wider. But more importantly, their firewalls were redesigned to accept modern vacuum brake boosters that couldn’t be fitted to the ’54 models. These power-assisted Center-Plane drum brakes were the equal of Ausco-Lambert’s earlier offering — at a fraction of the cost.

As for Ausco-Lambert Company, the May 1955 issue of Motor Trend magazine contains an interesting one-page news item called “Progress on Wheels.” Written by MT associate editor Jim Lodge, the article outlined the Ausco-Lambert brake system — and yet made no mention of its use on thousands of 1949–54 Chrysler vehicles. Another interesting detail is the description of the outer housing as being made of lightweight aluminum (those installed on Chryslers were cast iron). The story describes how Ausco-Lambert was hoping to offer its novel disc brake system (now referred to as “Double Disc Brakes”) as an over-the-counter upgrade for car owners looking for improved braking. The idea didn’t take off, and besides, European brake specialists had already discovered the floating-disc layout to be superior — and the way of the future.

Getting back to the tattered yet somehow still elegant 1953 Crown Imperial featured in this story, it has been verified as being one of the two units delivered to the Eisenhower administration by Chrysler. This one (VIN 7816130) was mostly utilized by Mamie and shows a mere 44,590 miles on the odometer. Its twin (Ike’s car) is currently in France and is also unrestored, though its original 331-cubic-inch Firepower HEMI® V-8 has been replaced by a 318 poly-head V8. Speaking of engine swaps, Mamie’s car was also given something of a heart transplant. In 1956 it was returned to Chrysler where its original 331 2-barrel Firepower and 2-speed Powerflite automatic transmission were exchanged for the latest 354-cubic-inch Firepower HEMI V-8 (with single 4-barrel carburetor) and push-button controlled 3-speed Torqueflite automatic transmission.

Not offered in 1953, the 4-barrel carbureted, 280 horsepower 354 Firepower HEMI® was part of a 1956 re-fit performed by Chrysler. The 354 added a full 100 horsepower boost over the car’s original 2-barrel equipped 180 hp 331 HEMI®. Interestingly, Chrysler stamped the 354 engine block with the same serial number used on the original 331.
Not offered in 1953, the 4-barrel carbureted, 280 horsepower 354 Firepower HEMI® was part of a 1956 re-fit performed by Chrysler. The 354 added a full 100 horsepower boost over the car’s original 2-barrel equipped 180 hp 331 HEMI®. Interestingly, Chrysler stamped the 354 engine block with the same serial number used on the original 331.

After the factory-blessed upgrade, Mamie’s limo was returned to the White House motor pool and continued to serve various purposes right through Ike’s final year in office (1961). Its history since then involves its sale (at auction) to a U.S. Marshal in the mid-sixties. Later, the stately machine turned up at a Chrysler dealer in Braintree, Massachusetts, and was a frequent sight on the streets of Boston. By 1998 the car was in the care of a Massachusetts car collector who inquired with the U.S. National Archives and Records Administration and confirmed its presidential provenance, as described in this story.

Today, the car’s fate is uncertain. Though there’s no threat it’ll be dismantled or otherwise permanently lost, years of marginal storage have caused serious deterioration. I discovered the car while leafing through a cars-for-sale magazine in December of 2013. I called the seller and got permission to visit the car at its Salisbury, MA, resting place. The owner, an older salvage yard owner named Charlie allowed me to take photos of the car as well as a 1950 Crown Imperial limo, which was also equipped with Ausco-Lambert disc brakes.

Steve Magnante is a professional automotive journalist and host for automotive television programming. Steve has been a staff member/frequent contributor to magazines including Chrysler Power, Mopar Action, Mopar Muscle and many others. You can find more stories like this one at the Redline Dodge blog, where Steve is currently a contributor.