What rear gear did your 1985 mustang come with?

My 1985 Mustang didn't come with *a* rear gear; it depends on the model and options. A 1985 Mustang could have had several different rear axle ratios depending on the engine, transmission, and trim level. Common ratios included 2.73, 3.08, and 3.27. Some performance options might have even had a 3.55 or 3.73. There's no single answer without knowing the specific vehicle's options.