Ford Differentials. Joseph Palazzolo
bearing size on the left and the large Torino style on the right."/>
Here is an example of 11 x 2¼-inch drums brakes with the small bearing size on the left and the large Torino style on the right.
The Ford 8.8-inch axle has the same ring gear mounting distance (see Chapter 7) for all ratios, just like the 9-inch. So again, unlike the GM and Dana axles that require a unique differential with different ratios, the Ford 8.8-inch differential is common across all of the ring-and-pinion ratios. There is a ton of aftermarket support for this axle (see Chapters 3 and 4 for more details).
The large bearing size was available with five different brake drum widths. Four of the 11-inch-diameter versions are pictured: 1¾ inches (top left), 2¼ inches (top right), 2½ inches (bottom left), and 3 inches (bottom right). A 2-inch version is not shown.
The 8.8 is a traditional semi-float Salisbury axle with C-washers for axle retention. Many people prefer to just call it the Ford 9-inch-style wheel end. But to be correct, it is a 3/4 float. There are 8.5-inch gears installed in these housings for lower-power vehicle applications. The typical 3-inch-diameter tubes can be a bit flimsy in higher-power applications.
Along with the many different brake and wheel end varieties, many different styles of axle shaft ends were manufactured. Some have only one access hole for the backing plate bolts, while others have three. Most have the two driving holes for the manufacturing process while one has a more square looking drive end. None of which changes the strength of the axle shaft. There are even different drum brake registers.
The Lincoln Continental style of disc brakes use 11½-inch rotors. In the 1980s and 1990s, the Lincoln Versailles brakes and complete axles were highly sought after because it was the only way to get a 9-inch axle with discs in a 58-inch-wide axle package. At this width, many were used in street rod applications without modification. With so many better performing aftermarket options today, there is no reason to use these marginal brakes.
This is an example of the only Ford 9-inch version that utilized one-piece tubes. Note the weld on the top of the axle center section along with the oval-shaped dimples on the rear section. The tubes do not have any welds, and you just see the witness marks of the parting line for the dies on the tubes. This was offered on the 1960 F-100 truck.
The Mustang Shelby GT housing is an easy one to spot, albeit rare, because it has extreme tapering of the axle tubes at the ends. There was a desire to have the stronger, larger tubes near the center of the axle but still retain the narrower tube ends for the wheel ends and the unique Shelby suspension brackets.
Some axle shafts can be shortened and a new spline machined in place. The 28-tooth axle shafts are typically tapered and cannot be shortened. Most 1972 and earlier 31-tooth spline shafts can be shortened and 1973 and later versions typically cannot be resplined. Here is a picture of the milling machine cutting new spline teeth after the axle has been cut to length.
Besides the styling of the Ford Edsel, even the axle shafts were very unusual. These shafts had a longer brake spacing offset and a unique brake drum register diameter of 2.870 inches, which was uncommon for the time. (It was later used for pick-ups and Broncos.) These axles even have a unique bolt pattern of five on 5 inches. I guess this helps add to the splendor of the vehicle.
From my piles of rare parts, here is an independent cast-iron 8.8-inch carrier axle. Note the ring diameter cast into the housing above the pinion.
The Lincoln LS and Jaguar S-type were equipped with an 8-inch, cast-aluminum, independent-style carrier. Notice the 8.0-inch ring gear diameter cast into the rear cover below the fill plug. Also notice the part number and metal axle tag. The bar code is present on this unit as well, although later axles just carry the bar code and the metal tag is no longer required.
Ironically, 8.0-inch independent carriers were made in cast iron. Here is an example of such a unit.
The Ford Explorer uses an independent-style carrier made out of cast aluminum. The ring gear speed sensor is shown in the upper right-hand portion of the photograph. This sensor is for the anti-lock brake system.
The 8.5- and 8.8-inch gears have even found themselves in the independent-carrier-style axles. The Ford Mustang and Thunderbird used this style for a few model years. There were also 8-inch ring gear independent carriers in production.
While the majority of this book focuses on rear-wheel-drive applications, there are also four-wheel-drive applications of the Ford 8.8-inch and 9-inch axles. When used in these applications the axles are very similar to a rear axle except they have a different wheel end arrangement that allows for the steering knuckles to be mounted.
When these axles are used to drive the front wheels, the hypoid gear set is basically flipped over and special reverse-cut tooth geometry is utilized for the 8.8-inch version. Reverse cut just means that the spiral hand is the opposite of traditional ring gears for a rear axle application; it is the mirror image of a standard rear axle gear (see Chapter 3).
This means that the standard 8.8-inch rear axle gears cannot be used for a front axle application and vice versa. During the manufacturing process, the gear blank forgings and the gear design are the same; just the spiral angle is machined to the opposite hand.
Reverse-Rotation Gear Set
The most common 8.8-inch front axle