I could potentally add a partial grill block to the lower grill, even under worst case desert heat conditions and maintain proper temps.
Will speak to the obvious here:
Testing will need to include truck loaded to GVWR for solo runs. And towing a representative trailer maximum (weight, frontal area, length), properly hitched, for GCWR.
I suggest the following. For anyone's testing.
The
SAE J2807 standards (a snippet) include:
Highway Gradeability
To merit a particular TWR (Tow Weight Rating), a vehicle must be capable of maintaining a minimum cruising speed while climbing the grade at Davis Dam on State Roads 68 and 163 in Arizona & Nevada. This 12-mile-long run originating in Bullhead City, Arizona, involves grades that vary between 3- and 7-percent with an average over 5-percent. During this test, the minimum acceptable ambient temperature is 100-degrees F, and A/C systems must be operating on the maximum cold setting with no recirculation and the blower at the highest possible setting.
Single rear wheel vehicles must be able to maintain an average of at least 40 mph on this grade at GCWR.
To pass these hot-ambient-temperature, steep-grade challenges, there can be no vehicle component failures, no warning lamps, and no diagnostic codes alerting the driver. In addition, the tow vehicle cannot lose any engine coolant. The vehicle under test must be equipped with the lowest numerical axle ratio available from the manufacturer.
A similar "run" may be closer to home.
Vernier Control Cable
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