STEMCO Hub Seal and Hub Cap Selection

STEMCO has provided the trucking industry with reliable hub seals for more than 40 years. Throughout our history, we have recognized the need for tougher, longer life seals that meet the performance, design and price requirements related to selecting the right seal for any fleet. To meet that need, STEMCO has engineered a menu of sealing options designed to meet the varying performance expectations of each fleet, all in an effort to maximize performance and value.

We will be referencing the following STEMCO PDFs:

Selecting the right STEMCO seal for the right application

  • Discover® is designed for the long haul carrier seeking high performance components. The Discover seal is an excellent choice for fleets running outboard-mounted drums that allow brake changes without seal replacement. The long life characteristics of this seal, proven in testing that exceeds competitive products’ performance by five times, make it the industry choice for performance driven fleet managers.
  • The Voyager® seal is designed for regional route trucks, city delivery and coach applications. Rugged design, simple installation and proven performance make Voyager the right choice for fleets looking for a superior brake job-to-brake job seal. In the everyday stop-and-go traffic environment these vehicles experience, the Voyager seal is the best value.
  • The Guardian® HP is the standard seal for trailer and axle original equipment manufacturers. The axle installation is durable and unique, and has proven successful for more than 40 years. Today, its enhanced features offer improved cost-per-mile performance. With simple one-step axle installation, Guardian HP is the seal of choice in the trailer industry.
  • Grit Guard® is always rough and ready and has endured more than forty years of dirty, unfriendly road environments that destroy wheel end components. So with this sixty year plus track record of performance, Grit Guard endures where others fail, and is still the choice for fleets working in grueling environments.

STEMCO Hub Cap Selection

STEMCO, the industry leader in hub caps, has developed a comprehensive offering of hub caps for all applications. To meet the performance, design and price requirements of today’s national and international fleets, STEMCO has developed a menu of hub cap options for both oil and grease applications. The product line has evolved into product specific technology developed to eliminate contaminants in abusive environments.

  • The traditional aluminum series 340 and 343 provide durability with the trademark red plug to allow venting of the hub cap. Using cast aluminum for constructing the hub cap body prevents warpage and provides superior durability and heat dissipation properties. The trucking industry recognizes STEMCO hub caps as the benchmark.
  • For grease applications, the 342 series Dirt Exclusion Hub Caps provide the same 340 casting without a side fill plug, plus a solid window with a sintered metal vent for venting purposes. To further support grease wheel ends, STEMCO developed the 352 series Solid Aluminum Hub Caps with a duckbill vent inserted in the face of a solid hub cap.
  • STEMCO Stamped Steel grease hub caps are manufactured from 14 gauge
    steel and have a protective yellow chromate plating with a clear lacquer coating for additional protection from corrosion. For synthetic base grease like Mobilith SHC™ 007, use the vented 340-5096 version cap. For petroleum base grease use the non-vented 340-5097 cap.
  • STEMCO PSI hub caps are available in both oil and grease for several popular applications. The oil hub caps have a side fill plug and a standard window with oil fill lines. The grease hub caps do not have a side fill plug and incorporate a gray opaque window with no markings. The PSI tee fitting and flapper valve are to be installed in the center of the hub cap and are available from PSI as a part of the PSI System.
  • Sentinel® Technology provides an unmatched filtering system to eliminate contamination of lubricant from grime, dirt or water. STEMCO provides four options to put Sentinel Technology to work for you: The Sentinel Hub Cap provides a tamper proof system for maximum protection and maintenance-free performance.
  • Integrated Sentinel hub caps integrate the Sentinel features into the window with fewer components and greater wheel end visibility. The Sentinel ESP (Extended Service Plug) and Sentinel ESP Filtered Vent allows economical retrofitting of wheel ends and drive axles with the benefits of STEMCO’s exclusive Sentinel Technology.
  • Defender composite hub caps offer superior corrosion protection and are available in oil and grease applications. Defender comes in a wide variety of vent options from our trademark red plug, to our Sentinel ESP plug, or our Integrated Sentinel Technology. For applications running in the most grueling conditions use the Defender to defend your wheel end.

If you would like more information on STEMCO hub caps or hub seals, visit our product pages.

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For in-depth articles covering industry news and trends, product spotlights, case studies, customer insights, and “thought leadership” topics from STEMCO professionals, visit The Wheelhouse Blog.

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TQM Wheel End Part 2 – Discover®/Voyager® Installation

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