GM Wheel Hub Bearing Torque Specsby Floyd Drake III
A truck's wheel assembly takes a lot of knocks and abuse, requiring it to be sturdy and reliable. A GM wheel assembly contains the tire rim, braking system, tire and the hub bearing, with the hub assembly being the key to the entire unit. Since the wheel is attached to the hub, adhering to proper torque specifications is necessary for the entire wheel to operate safely. Proper torque specifications for individual GM models should be obtained from their specific service manuals, or torque specification listing.
A wheel hub holds the wheel onto the vehicle and the hub bearing, located at the spindle of the wheel hub, allows it to spin freely. Wheel hubs come in three basic variations: hub assemblies with maintainable bearings, assemblies with replaceable, press-in bearings and enclosed hub units which require a complete hub unit replacement when the bearings wear out.
GM Torque Basics
Torque is the process of applying force to an object, in this case, the bolts holding the hub to the vehicle. This is measured using a torque wrench, which identifies the amount of force in foot pounds, and depending on the GM vehicle model, there are different torque specifications. GM determines individual torque specifications for its vehicle models to the weight, drivetrain type and intended use; the specifications determined are what GM considers to be sufficient to properly and safely hold the wheel on the vehicle, which is why similar vehicles have different torque specifications.
GM Automobile Torque Specifications
The range of torque specifications for GM vehicles varies between front and rear wheel drive vehicles; a 1997 to 1999 front-wheel drive Cadillac Deville requires 118 foot-pounds of torque on the wheel hub, whereas a front-wheel drive 1979 to 1985 Eldorado requires 176 foot-pounds of torque. The torque specifications for GM wheel hubs generally range between 107 to 225 foot-pounds, depending on the year and model.
GM and Chevrolet Truck Torque Specifications
Truck wheel hub torque specifications also vary greatly, with the majority of torque requirements for both GMC and Chevrolet trucks between the 155 to 180 foot-pound range. Variations in the drive system type can make for marked torque differences. For example, 1995 to 1997 GMC Jimmys require 180 foot-pounds of torque, but the wheel hubs on 1997 to 2001 Jimmy four-wheel drive models require 103 foot-pounds of torque.
A native of New Haven, Conn., Floyd Drake III began writing in 1984. His work has appeared in the "New Haven Register," Medford's "Mail-Tribune" and the "Ashland Daily Tidings." Drake studied journalism at Southern Connecticut State University. After working as a reporter in Oregon, he is now based back home in New Haven.