Turbulence on the Road to Air Suspension

1957 Cadillac Eldorado Brougham 

2000 Continental

The theme of automotive history repeating itself continues with my little post today about engineers and the buying public's desire to ride to ride on a cushion of air.  This excludes many sports car enthusiasts and modern motorists who never experienced a traditional big American car ride.

What I thought I knew about air suspension off the top of my head was that it was first used on GM's rolling palace, the $13,074.00 Eldorado Brougham of 1957-58.  The system developed more leaks than a cheap diaper, and most were converted to coil suspension.  Despite this failure, Buick offered a four-wheel "Air Poise" system on its 1958 models which made these "flivvers that simply drip with chrome" (to paraphrase a lyric sung by Frank Sinatra) handle worse than their coil sprung counterparts!  Air suspension became a short-lived late 1950's fad offered by many American companies including American motors!  Some competing systems were  for the rear wheels only, others for all four wheels.  In my opinion, the rear-only systems were more for load leveling than for increased comfort.  It was an option wisely ordered by few.  Cadillac still installed it on Eldorado Broughams until 1960.  Ironically, Lincoln, seeing the difficulty GM was having in the field with their system, abandoned plans to offer it on the 1958-60 Lincolns and Continentals, a car with plenty of engineering issues as it was.

Fast forward several decades and Lincoln decided to employ air suspension to make what, in my opinion were already the softest-riding, quietest cars on the road ride even softer and were also for load leveling.  This time out, the system held up (no pun intended) much longer, but inevitably developed leaks after several years.  If you have a Lincoln that's dragging it's butt like Fido across your new carpet, there is a solution:

Modern Lincolns, Air Suspension, Issues and Solutions:

 Interview With John S. Harroll of Lincoln Land

What year did Lincoln start offering air suspension in the modern era. Your conversion kits go back to 1990. Is that the first year?

Actually it was 1984 on the Continental and Mark VII vehicles on all 4 wheels. There was an option on the Town Cars for a rear air assisted leveling system that was integrated into the rear shock on the 85-89's. 1990 was the true air suspension, rear only on the Town, all 4 Continental and Mark. Rear only continued on the Town through the end of production. The 98 Continental was a split year, early cars had a 4 and later just rears. They continued with just rear on the Continental until production ceased with the 2002 model year. The most troublesome and costly was the 88-94 Continental 6cyl. FWD cars. They used an air strut on all 4. Components to retain the air suspension system are pretty much non existent for 88-94 Continental so conversion is the only route. Same situation with front air struts on 95-8 Continental, as well as fronts for Mark VIII.

My first new car was a 1988 Mercury Sable. It had the same 3.8 V-6 as the 2nd generation Contintental and I assume was built on the same platform as the Taurus and Sable. I remember telling a man I had the same engine as his Continental. I remember he didn't seem to appreciate that comparison. I really liked my Sable and should have driven it into the ground. If I bought just the springs for the Continental or Town Car (if I had one), what other components would I need besides the shock of my choice?

On a conversion for the rear on Town car 90 forward or Continental 95-02, all that is needed is the springs.Town cars never had air suspension in front.

Other Milestones In The Development of Air Suspension:

• William W. Humphreys patented an air suspension as early as 1901.  
• In 1920 George Messier developed an aftermarket pneumatic suspension system. Cars bearing his name made from 1922 to 1930 used the system.  It was described as riding on four gas bubbles (burrrp!). 
• Air suspension was used on heavy aircraft during WWII in order to save weight and allow compact construction.  It was also used in trucks for self-leveling purposes.  The axle height stayed the same, regardless of vehicle load.  
• The Stout Scarab featured air suspension at all four wheels.
• In 1952 GMC developed a durable and reliable air suspension system for its busses, which inspired them to try it on cars.  Simply downsizing the bus system was deemed impractical and a separate system was developed for cars.
• Though not pure air suspension, Citroen must be cited for its air/oil hydropneumatic suspension that made its debut on the rear wheels of the top-of-the-line Traction Avant 15 "Hydraulique" model in 1954.  In 1955, the system was used on all four wheels of the most beautiful thing to come out of France since Brigitte Bardot, the DS.  These cars remained in production for 15-plus years.  Charles de Gaulle credited one with saving his life during a 1962 assassination attempt.  "DS" was a play on words.  Pronounced "Day-ess", it translated into the French pronunciation of "Goddess". 

• Packard gets an honorable mention for it's self-leveling, four-wheel torsion bar suspension system, which also appeared on the 1955 models, even though this was purely electrically-controlled.  The company sold some 70,000 units that year, giving hope to a company that was on the ropes and down for the count like one of Muhammad Ali's opponents.  They even pulled-off an attractive facelift of the 1951 "High Pockets" body and a modern OHV V-8.  Their were problems with the system and the engine and that made 1956 the last year of a true Packard.

• In 1960, the Borgward P 100 was the first German car with self-levelling air suspension.
• In 1962, the Mercedes-Benz W112 platform featured an air suspension on the 300SE models. The system used a Bosch main valve with two axle valves on the front and one on the rear. These controlled a cone-shaped air spring on each wheel axle. The system maintained a constant ride height utilizing an air reservoir that was filled by a single-cylinder air compressor powered by the engine. In 1964, the Mercedes-Benz 600 used larger air springs and the compressed air system also powered the brake servo.
• Rolls-Royce incorporated self-levelling suspension on the 1965 Rolls-Royce Silver Shadow, a system built under license from Citroën.
• In 1975, the Mercedes-Benz 450SEL 6.9 incorporated a hydropneumatic suspension because the patents on the technology had expired. This design replaced the expensive, complex, and problematic compressed air system that was still used on the 600 models until 1984.
• In 1986, Toyota Soarer introduced the first electronically controlled (TEMS), a semi-active full air suspension (spring constant, variable attenuation force).
• Dunlop Systems Coventry UK were also pioneers of Electronically Controlled Air Suspension (ECAS) for off road vehicles - the term ECAS was successfully trade marked. The system was first fitted to the 93MY Landrover Rangerover.
• In 2002 the GMT 360 Trail Blazer SUV featured rear air assist air suspension with Dunlop air springs and an integrated Wabco control system.
• In 2005 the GM H2 HUMMER featured an optional rear air suspension system with a dual compressor control system from Dunlop to support tire inflation for off road applications.

Credits and Bibliography:

John S. Haroll, of Lincoln Land, Clearwater, FL

Wikipedia

Lincoln: Sixty Years of Excellence, by Thomas E. Bonsall

Pontiac: The Complete History: 1926-1986, also by Thomas E. Bonsall

Cadillac: Standard of the World, by Maurice D. Hendry with the Editors of  Automobile Quarterly

The Buick: A Complete History by Terry B. Dunham, Lawrence R. Gustin and the Staff of Automobile Quarterly

Photos by Neil Settle c2017