Underhood: Subaru Brake Grease Goes Under the Abutment Clip
There are inherent CV axle problems associated with the boxer engine design. This video is sponsored by TrakMotive.
Subaru is an increasingly popular vehicle in the U.S. and has more than doubled its market share in the past 10 years.
At the heart of every Subaru vehicle, you’ll find the Subaru boxer engine. Unlike most engine designs, such as inline and V-type, the boxer engine features pistons that move in opposition to each other due to its unique horizontal layout resulting in balanced, smoother operation that helps overall’s vehicle safety and longevity.
However, there are inherent CV axle problems associated with this engine design over time. Here’s where the OE CV axle design problem lies. These CV axles rely on the inboard joint to provide linear travel or plunge for the CV axle. This limits the maximum angle this type of CV axle can operate at without binding, up to 23 degrees for a tripod style and 30 degrees for six ball style joints. It also limits the amount of linear travel the CV axle is capable of, which is roughly two inches.
The OE CV axle creates a binding issue when installed on vehicles where the transmission either has shifted excessively from center or experiences excessive side to side movement during acceleration. There is a solution with the new Subaru HD CV axle. The design enhancements include increased linear travel and greater articulation to compensate for worn or fatigued engine and transmission mounts.
Moving the linear or telescopic function of the CV axle from the inboard joint to the center shaft allows the use of six ball joints with a full 45 degrees of articulation on both sides. It also allows up to 50% more linear travel than the OE CV axle.
The Subaru HD CV axle design eliminates binding issues encountered on vehicles where the transmission has either shifted away from center or experiences side to side movement during acceleration. Additionally, always make sure to inspect Subaru engine mounts when doing drive line repair to avoid additional vibration issues.
Subaru transmission mounts are susceptible to becoming very spongy and wear out due to the unique horizontal movement of a boxer engine. When these mounts wear, they cause the engine and transmission to sit slightly off center. Make sure to inspect and replace the transmission amounts if they’re worn to eliminate off center vibration issues.
Keep in mind, if the mount is worn, the articulation angle of the new replacement axle becomes the mount that is holding the transmission in the correct location, which creates a binding vibration. Thanks for watching. We’ll see you next time.
This video is sponsored by TrakMotive.