American Axle & Manufacturing Inc. (AAM) has added a new 4.56 ring and pinion gear set. The OEM-designed 4.56 gear set ratio (AAM part #40005988) is made for the 11.5-inch rear axle used in 3/4- and one-ton 2003-2013 Ram and 2003-2014 Chevy Silverado and GMC Sierra trucks.
AAM ring and pinion gear sets are made using “two-cut” gear manufacturing processes to ensure the lowest tolerances possible for the quiet operation required by the company’s OEM customers, the company notes. This two-cut design also allows for easier set-up for aftermarket replacement.
“The combination of materials, heat treating and gear geometry allows for a gear set that has 10 times the life of some non-OE gear sets,” says Greg Marsh, AAM engineering manager. “The strength of our materials, the elimination of noise, and the ease of installation add up to a superior gear set for the aftermarket.”
Marsh says one of the advantages of AAM gear sets is saving technicians’ time with a first-time, proper fit installation. He says machining tolerances held in AAM plants are so tight that most AAM gear sets can be installed into the vehicle, with rarely the need to change the original pinion shim.
AAM offers customers bearing or master install kits that come with the necessary components to complete the installation. The bearing kits contain all four differential bearings. The master install kits include the remainder of the components needed such as ring gear bolts, hub bolts, hub and cover pan gaskets.
AAM also offers additional components for the new rear 4.56 gear set such as an aluminum cover to reduce temperatures in high horsepower applications and front 4.56 9.25-inch gear sets for four-wheel-drive vehicles.
When technicians install the 4.56 gear set, Marsh recommends they replace all of the parts necessary including the bearings using AAM kits #74067011 (bearing kit Ram 2003-2013, GM 2001-2010), #74067018 (bearing kit GM 2011-2014), #74010015 (master install GM 2001-2010), and #74010016 (master install Ram 2003-2013, GM 2011-2014). The bearing kits contain all four differential bearings. The master install kits contain the remainder of the components needed such as ring gear bolts, hub bolts, hub and cover pan gaskets, etc.
If the 4.56 gear set is being installed in conjunction with a lift kit, many customers like upgrading their cover pan to a stylish aluminum cover that also reduces temperatures in high horsepower applications (available as #74030017).
If the 4.56 gear set is being installed in a 4WD vehicle, the corresponding front 4.56 9.25-inch gear sets are #40024878 (GM mounting distance) and #40022464 (RAM mounting distance).
For more information, visit www.demandaam.com.