A rear end, commonly known as a "rear differential" or "differential," is the part of a vehicle that transmits the torque produced by the engine into the wheels. Ford has installed several types of rear ends on its long line of vehicles. These rear ends are commonly installed on other vehicles because of their quality and ability to handle heavy loads of torque. Race car enthusiasts often equip and modify Ford rear ends in their performance cars.
The Ford 9-inch rear end differential is the most popular Ford rear end. It is often used by car racers and car technicians to power Mustangs and other race cars. It was produced from 1957 until 1985, and was equipped in several Ford cars, vans and half-ton pickup trucks. It can easily be identified by its bolt-less rear cover. Most car technicians find the 9-inch rear end ideal because of its removable carrier and because it was made without any carrier breaks. You can put a wide range of pinion and ring combinations that can range from 2.50-to-1 to 6.50-to-1. 9-inch rear ends were available in both 31-spline and 28-spline axle shafts.
The Ford 8-inch rear end is the 9-inch rear end's little brother. It was specifically designed for light-duty vehicles and offers stability and good control for mid-level speeds. It was also designed to be easily removable. There are two generations of the 8-inch rear end, one made from 1962 to 1966 and one that was made from 1967 onwards. The latter generation is considered to be stronger because its pinion pilot was made with better design and more iron. The 8-inch was only available with a 28-spline axle shaft.
The 8.8-inch type is usually used as an alternative to the 9-inch rear end. Car technicians compare this Ford rear end to the Chevrolet 12-bolt rear end. This variant is also one of the most available rear ends in junk yards and chop shops, allowing a budget-conscious technician to buy a cheaper alternative to the 9-inch rear end. It is durable and light, and most vehicles equipped with the 8.8-inch model came standard with an integrated, limited-slip differential known as the "Traction-Lok." Its gear set ranges from 3.08 to 5.14, and it utilizes a 30-spline axle shaft.
