Shopping Cart

No products in the cart.

SAE J 1489:2000

$25.35

Heavy Truck and Bus Retarder Downhill Performance Mapping Procedure

Published By Publication Date Number of Pages
SAE 2000-05-01 17
Guaranteed Safe Checkout
Categories: , ,

If you have any questions, feel free to reach out to our online customer service team by clicking on the bottom right corner. We’re here to assist you 24/7.
Email:[email protected]

The procedure covers the estimation of the total retardation capability available to a specific vehicle from:

  1. a

    Natural retardation (rolling resistance, aerodynamic drag, etc).
  2. b

    Engine drag
  3. c

    Engine, integral automatic transmission, driveline or trailer-axle retarders
It assumes that foundation brakes are not used for maintaining speed on long mountain descents. Retardation is rated in terms of the maximum grades on which stable control speeds can be maintained for each gear over the range of highway speeds appropriate to that gear. For each gear, the calculation procedure determines maximum grades for at least four values of control speed ranging from the vehicle velocity corresponding to full load governed engine rpm, to the vehicle velocity corresponding to the engine rpm at minimum (idle) speed. In addition, the calculation procedure provides information on the total retarding power available for each gear.
SAE J 1489:2000
$25.35