OK.
Here goes.
I was partially wrong. Jabber is partially wrong.
Mopar uses 44mph as the fan disable speed, not 35mph (that's Ford)
I work on 200 different models of cars, so I get things swapped in memory sometimes.
If you hear fans running at highway speed, you are hearing the AC operation. The cooling fan operation is disabled above 44mph, except in emergency overheat situations.
As for a service manual being wrong.... I am the 4th generation in the automotive business in my family. We learned to trust in the best source of information as far back as 1909.
There can be typos. I'm the guy who got the PT service manual changed for the spark plug torque specs after the 2001 manual printed a typo.
Here's the chart from page 7-55 of the 2002 service manual.
