The 35-MPH Curve With a Trailer
At 6:40 a.m. in October, you are westbound on a two-lane county road in northern Michigan. The posted limit is 55 mph. A yellow diamond curve sign with a 35 mph advisory plaque stands 500 feet before a right-hand bend. Below it, a yellow plaque reads SLIPPERY WHEN WET. Overnight rain has left wet leaves on the pavement. You are driving a mid-size pickup towing a 3,500-pound utility trailer at 45 mph. A logging truck is close behind. Sight distance through the curve is about 250 feet, and there is no shoulder. As you enter the bend, you feel a slight side-to-side movement from the trailer. The road has a double yellow center line, and oncoming traffic occasionally appears. You have not braked yet.
1. Is the 35 mph advisory plaque a legal maximum speed? Can you be cited for traveling 45 mph?
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The 35 mph plaque is an advisory speed, not a black-on-white regulatory limit. It is the highway agency’s estimate of a reasonable speed for the curve under good conditions. It does not by itself make 36 mph illegal.
But Michigan’s basic speed law requires a speed that is reasonable and prudent for the actual conditions. At 45 mph with wet leaves, only about 250 feet of sight distance, and a 3,500-pound trailer, your stopping and steering margin is reduced. An officer could cite you for too fast for conditions even though you are under the 55 mph limit. The advisory and the SLIPPERY WHEN WET plaque are evidence that 45 is too fast; they do not create a safe harbor.
2. What should you do about speed and the truck behind you before and inside the curve?
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Slow down before the curve, not in it. Ease off the accelerator and brake gently while straight, aiming for 35 mph or less-perhaps 30 mph-before the bend. In the curve, keep a steady line and avoid hard braking or sudden steering, which can start trailer sway. If sway begins, release the accelerator and hold the wheel steady; do not jerk the wheel or brake hard.
The logging truck behind you does not justify carrying extra speed. With no shoulder, do not stop in the curve to let it pass; maintain a predictable speed and let it pass only where a safe pullout exists.
3. The road has no posted minimum speed. Is slowing to 30 mph illegal?
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No. There is no posted minimum, and the basic speed law permits a lower speed when conditions require it. A 30 mph approach on wet leaves with a trailer is reasonable, even if it annoys the driver behind. You must not drive so slowly as to impede traffic unreasonably, but safety for the conditions is the standard.
The truck’s decision to pass on a blind curve would be the truck driver’s responsibility and a dangerous choice; you should not speed up to prevent it. Keep right as much as the lane allows and maintain a steady speed.