See also:

Gross Combination Weight Rating (GCWR)
The GCWR is the total permissible weight of your vehicle and trailer when weighed in combination. NOTE: The GCWR rating includes a 150 lbs (68 kg) allowance for the presence of a driver. ...

Fluid Capacities
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LOW
This range should be used for engine braking when descending very steep grades. In this range, the transmission will downshift for maximum engine braking, and upshifts will occur only to prevent ...