• A Ford 8.8 is an axle system used on a variety of Ford vehicles. The 8.8 axle gives the vehicle more strength for better off-road capabilities. Not all vehicles are outfitted with disc brakes, but if an 8.8 axle is included, disc brakes are as well. The Ford 8.8 is a favored axle system that some vehicle owners install in place of the standard axles whether their vehicle is a Ford or not.
  
  

Complete Assembly

• The complete assembly for an 8.8 is 174 pounds (including brakes). The outer diameter (OD) of the tubes measures 3.25 inches and the tube thickness is 0.250 inches, although some are narrower at 0.188 inches. The ring gear diameter is 8.80 inches (thus the name); ring gear bolts are 7/16 inch in diameter and require a quantity of 10. The pinion diameter splines are 1.32/31, and the rotor thickness where it attaches to the axle is 0.250 inches. The overall width is 59.625 inches. Spacers can be added to accommodate a shorter truck width.
  
  

Pinion and Spline

• The hole diameter for the anti-locking brake system (ABS) sensor in the housing top is 0.811 inches and the bolt size, U-joint flange to the yoke, is 12 x 1.75 x 30 mm.. The pinion is a gear that has a small number of teeth designed to mesh with a larger wheel. A spline is a groove on the side of a shaft, and when two splines work in parallel, power is transmitted between two rotating elements. The more splines an axle has, the great diameter the axle will be, resulting in more load bearing capacity.
  
  

The Axle

• The 8.8 axle uses C-clips to keep the shafts in place. The clips are inserted into the side gears of the differential and slide over the end of the axle. The C-clips have a tendency to break rather than just bend upon incident, causing the axle to fall out of the axle tube. The axles are also fitted with the Trac-lok limited slip differential. The Trac-loks are also known as lockers.
  
  

The Price

• A Ford 8.8 axle, if not installed on the vehicle, will cost anywhere from $400 to $1,200. The price will vary depending on whether it is new or used. Additional costs will be having it installed and buying some of the parts used in the axle.