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Vehicle Speed Parameters
Disadvantages:
Not setting VSL allows the truck operator to “run fast”
and as a result get poor fuel economy. Also, some
drivers may not like driving with Soft VSL enabled.
Some common complaints are that there seems to be
lower power and the truck may not feel like it can hold a
constant speed. However, these effects are due to the
modulated fuel delivery, and once a driver gets used to
them, will still result in the advantages listed previously.
This perceived power loss can be even more noticeable
on trucks that are spec’ed near minimum gradeability
requirements.
Recommendations:
✔ Do not use Soft VSL unless you expect the truck to
operate at or above VSL in uneven or fl at terrain.