One of the more underappreciated components of a turbocharger is its thrust bearing assembly. The thrust bearing is located at the compressor end of the turbine shaft within the center cartridge and is tasked with controlling axial motion as well as providing support for the shaft. It receives oil supply from the center cartridge, and ports present in the thrust washer allow the turbine shaft to essentially float on a layer of oil during operation. In extreme conditions such as high drive pressure or excessive shaft speed, this layer of oil can be displaced enough that the shaft comes into contact with the thrust washer (i.e. metal-to-metal contact), leading to premature wear and eventual failure.

What Is A 360-Degree Thrust Bearing, And What Does It Do?

Most conventional journal bearing turbochargers leave the assembly line with what is known as a 270-degree thrust bearing. This means that the thrust washer only encircles ¾ of the shaft. A 360-degree thrust washer completely encircles the shaft and has been a common, cost-effective aftermarket turbo upgrade for years now. The added surface area a 360-degree thrust washer provides improves durability in high drive pressure, high boost situations, along with offering added protection against surging (surge being a common side-effect of hanging a larger or heavier compressor wheel on the same shaft). This is why we offer a 360-degree thrust bearing upgrade option for every turbo we sell. The upgrade also comes standard on all chargers equipped with our SXE-R competition billet compressor wheels.

The Smeding Diesel Extreme Duty 360-Degree Thrust Bearing Option

Our extreme duty, 360-degree thrust bearing is made from steel rather than conventional brass. By starting with a superior material, our thrust bearing washer won’t wear as easily or extensively as a brass unit will—even if an inordinate amount of oil displacement occurs. In addition to its steel construction and the aforementioned complete cushion of oil surrounding the shaft, our 360-degree thrust washer features more oil ports to help mitigate oil displacement. Finally, our extreme duty thrust bearing boasts hydraulic ramping, which allows the bearing to resist the thrust forces (from both the compressor and turbine side) placed upon it. Simply put, it’s built to handle abuse.

 Is A 360-Degree Thrust Bearing Mandatory?

To answer the question above: No. The brass, 270-degree thrust bearing that comes standard in our turbos works perfectly fine for the average daily driver or tow rig—so long as the turbo is properly sized for your specific setup (engine size, fuel system mods, tuning). However, when pushed out of its engineered limit (displaced oil due to overspeeding, or overloading of the shaft), a 270-degree thrust bearing is much more susceptible to allowing the turbine shaft to come into contact with the thrust washer, which (again) leads to immediate wear and shortens the turbo’s life. Our extreme duty 360-degree thrust bearing is specifically designed to guard against premature wear, and for $175 offers customers affordable peace of mind.

Applications Where The 360-Degree Thrust Bearing Is Recommended

For competition applications such as sled pullers, where turbo size is limited and you’re forced to spin an undersized charger faster than you ordinarily would, the 360-degree thrust bearing is highly advised. Likewise, in a dedicated drag racer or even a weekend warrior, where big fuel and nitrous is often used to earn that target E.T. or high trap speed (and where excessive drive pressure, boost, and shaft speed are all in the mix), the 360-degree thrust bearing upgrade is highly suggested. For other applications, and namely high horsepower street trucks, there is nothing wrong with a little overkill. If, even periodically, you think you’ll be exposing your turbo to extreme conditions, it pays to have the 360-degree thrust bearing onboard to protect your investment.