What is the axle gear ratio for a 1988 mustang gt 5.0?

The axle gear ratio for a 1988 Mustang GT 5.0 wasn't a single, fixed number. It varied depending on the options selected when the car was ordered. The most common ratios were 3.55:1 and 3.73:1. Some cars might have had different ratios, but those two were by far the most prevalent. To know the exact ratio for a specific car, you'd need to check the vehicle's documentation (like the window sticker or owner's manual if available) or physically inspect the axle housing for a marking indicating the ratio.