Issue link: https://read.dmtmag.com/i/34500
BEARINGS Wheel-end bearings for trucks and trailers are typically the tapered roller type with either grease, semi-fluid grease, or oil level lubrication. Anticipated bearing life is compared by running an ANSI (American National Standards Institute) L10a test to statistically determine the fatigue life. The test variables are wheel end loading (amount and location), bearing end-play, tire and wheel weight, tire static loaded radius, and duty cycle (vehicle speed and turn frequency and lateral g loading). The output is L10a Weighted Bearing System Life in miles. The common belief among fleet maintenance technicians is that bearings do not fail or wear out in normal service unless subjected to loss of lubricant, excessive endplay, or excessive preload. Using standard bearings with a 2" wheel outset on a N-type spindle arrangement does reduce the L10a bearing life expectancy. Bearing manufacturers offer enhanced bearings for trailer and drive axle applications that provide L10a life with 2" outset single wheels near that of conventional bearings with dual wheels. These bearings have an extra roller with a slightly different contact geometry between the cup and cone and are machined to tighter tolerances and a smoother surface finish. Timken’s 454-Series wheel bearings*: ™ • One bearing for Dual and Wide Singles – Specially designed to handle the 2" outset loads – Allows consistency within fleet – Provides flexibility of wheel arrangements • Compatible with industry standard components – Use with popular axle and hub designs – Can retrofit onto existing equipment *For more information on the Timken 454-Series ® wheel bearings, visit The Timken Company at www.timken.com. IMPORTANT: Some wheel bearing assemblies have warranties that may be voided when the wheel ends are disassembled. Contact your axle and/or suspension component supplier before removing any wheel end components. Cone Cup MileMate Set* ® N Trailer Outer NP454049 NP454011 Set 440 N Trailer Inner NP454248 NP454210 Set 441 R Drive Outer R Drive Inner NP454580 NP454572 Set 442 NP454594 NP454592 Set 443 P Trailer Inner & Outer NP454445 NP454410 Set 444 *454-Series ™ ® ® registered trandemarks of The Timken Company. See www.timken.com/454wheelbearing for Limited Warranty information. is a trademark of The Timken Company. Timken and MileMate are the ™ ENGINE COMPUTERS / FUEL ECONOMY Tire revolutions and axle ratio are inputs to the Engine Control Module (ECM) to manage road speed. Changing from dual to MICHELIN ® To accurately determine fuel efficiency gains from switching to MICHELIN X One tires, it is ® X One ® tires may require changing the Tire Revolutions per Mile (Tire Revs./Mile) value in the ECM in order to ensure speed, distance, and fuel economy are accurate per indications. Reference the MICHELIN Truck Tire Data Book (MWL40731) for proper Tire Revs./Mile values for the MICHELIN tires you chose. ® X One ® ® ® recommended that SAE (Society of Automotive Engineers) Fuel Test J1376 be conducted to verify the values determined by the engine computer. New EGR (Exhaust Gas Recirculation) engines may use diesel fuel to clean the DPF (Diesel Particulate Filter). When checking fuel usage please be aware of the additional fuel used during regeneration of the DPF. 18 Truck Technical Specifications