Hub bearing unit 2

Cutting weight and costs since the '70s

In the early 1970s, Hub Unit 2 turned Hub Unit 1 functionality and experience toward industry demand for more compact, lightweight, cost-cutting solutions. Building on the HBU1 design, HBU2 incorporated a flange with the bearing outer ring.

Non-driven and driven wheel applications for medium-size cars

In the most common HBU2 application, the brake disc or drum and wheel are mounted to a rotating flange. A variant HBU2 design features a flanged ring mounted on the knuckle through threaded bolts. Hub Unit 2 is typically used with rotating outer ring for non-driven front or rear wheels.

Double row angular contact design

Hub Unit 2 features a double row angular contact ball bearing with matched rings and ball-sets to provide the required axial clearance. Contact angles are optimized to provide specific preload and withstand specific wheel load condition. Key features include:
  • Flanged outer ring designed as a lightweight structural component
  • Outer ring raceways are induction-hardened for bearing performance
  • Sealed for life with high performance, application-specific grease
  • Robust flange features threaded holes or studs and a spigot to centre and mount brake and wheel
  • Alternative designs are available for driven wheel applications
  • Available with ABS impulse ring mounted on the rotating ring

HBU2T: The go-to choice for light trucks

Offering full HBU2 functionality, HBU2T, features one tapered bearing, is becoming an increasingly popular choice for light truck driven wheel applications. In the majority of the applications the non- rotating flanged ring is mounted on the knuckle through threaded bolts.

The HBU2T with fixed outer ring is a solution alternative to single tapers or HBU1T in case of aluminium or light alloy knuckles; in these cases an alternative solution is the application of HBU3.2T, features a double row angular contact tapered bearing.
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