Although we've talked about Axle Nut Torque Specs, which apply to wheel bearings of course, we haven't talked specifically about bearings themselves. In many cases, the two are interchangeable terms, but this is not always the case and in that last article, we did not get specific about torque values.
The type of axle, the make and model of the vehicle and wheel bearing system, and the specific application will all determine the actual torque values for the wheel bearing. Most systems are generally the same for similar vehicles, however, and so a vehicle such as the 1990s Acura 2.x and 3.x series have the same axle on all models with the same torque specifications (181ft-lb at front, 134# at rear).
The ArvinMeritor Axle
Probably the most common high performance and after-market axle wheel bearing systems are the Meritor brand from ArvinMeritor. These are installed with two torque values (initial and final adjustment) and are generally the same no matter the application. They are common enough and general enough that they are a good example of common values for wheel bearing torque specs.
In the Meritor Conventional Wheel-End system, there are the following specifications:
- In drive axles with bendable or without lock washers, torque values are 200lb-ft initially, then back off one turn and add 50lb-ft for final adjustment and back off 1/4 turn.
- For front, non-drive steer axles torque value is 100lb-ft (back off one turn) and 20lb-ft (back of 1/3 turn).
- Trailer axles have the aforementioned 200lb-ft, 50lb-ft with the same back offs.
The much heavier-duty Long-Life Wheel-End Systems from Meritor have much higher torque specifications. These are generally used on heavier-duty equipment and vehicles:
- From non-drive steer axles have a 500-700lb-ft inner nut torque and a 200-300lb-ft outer nut torque spec.
- Trailer systems have a 700-750lb-ft inner and 250-300lb-ft outer nut torque.
- On the TRIAD Trailer system the initial adjustment torque is 150-200lb-ft, then back off until loose, and tighten to 50-60lb-ft and back off 1/8 turn.
- The TL Series trailer system has an 810-850lb-ft torque.
While the specs given above apply only to Meritor systems specifically, they are indicative of general industry standards of expectation on most well-made systems. Your service and maintenance manuals will have the specific requirements for your application.