Q: How do you fix an air ride suspension that has gone flat?

A. It depends on why the suspension went flat. Cadillac and Lincoln have used air-ride suspensions under their cars for many years. Other makes and models have air leveling suspensions that use air shocks and an onboard compressor to maintain ride height. If an air spring or air shock develops a leak (which most do after many years of service), the air spring or shock can’t hold pressure. It will leak and eventually go flat.

To make matters worse, a constant air leak at a spring, shock or air line causes the compressor to run constantly. The compressor is not designed to run constantly and sooner or later it burns out and fails from being worked to death. Consequently, if a compressor has failed, there is usually an air leak somewhere in the air ride suspension that needs to be found and fixed before a new compressor is installed.

Replacement compressors for some of these applications are hard to find, and expensive. The same goes for the air springs and air shocks. Once a vehicle is 10 or more years old, original equipment parts may no longer be available — and if no aftermarket replacement parts are available for the application (which is often the case with less common vehicles), the vehicle owner may have few repair options.

Used parts from a high-mileage vehicle in a salvage yard are risky, and new air ride suspension parts may cost more than an older vehicle is worth. The answer here would be a conversion kit that converts the original air spring or air ride suspension to a normal suspension with conventional springs and shocks or struts. Such kits are available for many of these older applications and offer an affordable alternative to replacing the original air springs, shocks or compressor.