The sixth generation of the Ford Mustang was introduced in 2015. The main change for this model year was a new platform - the S550. This is what makes a Mustang an S550.
The S550 Mustang is built on an all-new platform that is lighter and stiffer than the previous generation. The result is a more agile and responsive car that still has the same great looks and performance that we expect from a Mustang.
One of the most noticeable changes for the S550 is the new independent rear suspension. This gives the car better handling and a smoother ride. Another change is the addition of an optional 2.3L EcoBoost engine. This turbocharged four-cylinder engine provides excellent power and fuel economy.
Overall, the S550 Mustang is a great update to an already iconic car. If you're looking for a fun and fast sports car, be sure to check out the new Mustang!