2012 Mercedes GL 550 4MATIC suspension systems are great but when the 2012 Mercedes GL 550 4MATIC struts fail or the 2012 Mercedes GL 550 4MATIC air springs go out, it's almost impossible to drive. Find everything you need for your air suspension repair and maintenance at Strutmasters. Save even more money if you convert to our 2012 Mercedes GL 550 4MATIC conversion kit for a smooth and soft ride. No more sagging ride, leaking struts or bad compressor problems. The Strutmasters conversion kit with our Trademarked GlideRide Technology™, comes with cold wound premium american-made coil springs and specifically tuned gas struts to give you a ride as close to the factory air as possible.