Bronco Nation

Pitch & Role Accuracy

MIGeezer
Oct 26, 2026

Rank V

Yesterday at 2:38 pm

I was heading to the Manistee NF the other day. On a paved road and saw the sign to warn trucks of an 8 degree down hill road up ahead. So I kept an eye on the pitch & role to see what it read. It only showed 4 degrees. Just wondering how the road commission measures vs what is on the Bronco. I believe the one in the truck vs. the sign. We have a lot of smart folks on this forum. Does anyone understand how the road commission measures?

A learning experience!!
G Lusted

Rank 0

Yesterday at 8:26 pm

#1
You sure the road wasn't marked as a percent grade %? At least in CO that's the way the mountain passes are marked.

The bronco is degrees from level which isn't the same.


An 8% road grade corresponds to an angle of approximately 4.57°. This is calculated using the inverse tangent of the slope (rise over run), where an 8% grade equals 0.08, making the formula $\theta = \arctan(0.08)$.
Would you like the formula for converting any other road grade percentages into degrees?
G Lusted

Rank 0

Yesterday at 9:20 pm

#2
mfreel
You sure the road wasn't marked as a percent grade %? At least in CO that's the way the mountain passes are marked.

The bronco is degrees from level which isn't the same.


An 8% road grade corresponds to an angle of approximately 4.57°. This is calculated using the inverse tangent of the slope (rise over run), where an 8% grade equals 0.08, making the formula $\theta = \arctan(0.08)$.
Would you like the formula for converting any other road grade percentages into degrees?

Great math review! Thanks!
The road grade signs, nationwide, are a percentage of vertical travel over horizontal travel. The Bronco instrumentation reads degrees of pitch only.

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