Sagging suspension can be a result of air suspension struts and/or drier leaking air. These type of air leaks can lead to failure of the air suspension compressor.Google+
Car Problem Reports
Lincoln Town Car Compressor Failure Due to Air Leaks From Air Suspension Struts and Drier
Lincoln Town Car Problem
Average Mileage: 136,477 mi (10,000 mi - 260,000 mi)
Visitor, 2004 Lincoln Town Car, 51,500 mi
retrofitted with regular struts
Visitor, 1993 Lincoln Town Car, 180,000 mi
my air bags were cracking and leaking air so i replaced them with coil springs..
Visitor, 1997 Lincoln Town Car, 226,985 mi
Passanger side goes down when parked and air compressor runs all the time.
The ais suspension light is on, the rear is sagging, and I can't afford a big repair.
Visitor, 2001 Lincoln Town Car
pump ran all the time ,now it doesn'nt
Visitor, 1997 Lincoln Town Car, 10,000 mi
back end of car almost sitting on pavement. Visited dealer and it was fixed
Visitor, 2001 Lincoln Town Car, 146,000 mi
Suspension Compressor runs constantly when the car is started, rear end deflates when the car is turned off.
Visitor, 2004 Lincoln Town Car, 100,000 mi
I was driving my 04 and all of a sudden it went to the ground my rear end wtf.
@ 130k miles, every morning the driver side rear was sitting low. Starting car fixed it. 3k miles later, dash light "Check Air Suspension" would be on at start, until car was level. Leaky air bag. Lincoln estimate was $900 for repair, $700 for replace with springs. Caught it early, the compressor did not need replacing. Bought air bags & dryer rebuild kit on eBay. Works great. I recommend a new dryer, the rebuild kit takes too much time. Still need new shocks.
Visitor, 2005 Lincoln Town Car, 260,000 mi
vehicle has always taken bumps very hard