Driving safety guide · Ford of Peoria · Peoria, IL
Curve and Hill Warning Signs Explained
Curve, Turn and Winding Road signs, black and yellow chevrons, advisory speed plaques and Hill signs all warn you about the shape of the road ahead. Here is what the federal Manual on Uniform Traffic Control Devices (MUTCD) says about each one and when it is used.
The short answer
Curve and Turn signs are yellow diamond warning signs placed before a change in the road's direction; a Turn sign should be used instead where the curve's advisory speed is 30 mph or less. Reverse and Winding Road signs mark two or more curves close together. Chevrons on the outside of a curve guide you through it, and an Advisory Speed plaque with the warning sign shows the advisory speed for the curve. Hill signs warn of a downgrade ahead.
Warning sign basics
Shape and color: unless the MUTCD says otherwise, warning signs are diamond-shaped with a black legend and border on a yellow background.
What they cover: the MUTCD groups Turn, Curve, Reverse Turn, Reverse Curve, Winding Road, Hairpin Curve and 270-degree Loop signs as horizontal alignment signs. They can be used with Chevron Alignment signs, advisory speed plaques, delineators, pavement markings and rumble strips to advise drivers of a change in the road's alignment.
From the Manual on Uniform Traffic Control Devices (MUTCD), 11th Edition with Revision 1, Sections 2C.02 and 2C.05, read November 4, 2026.
Curve and turn signs
The MUTCD sets these uses for each horizontal alignment sign:
| Sign | When it is used |
|---|---|
| Curve (W1-2) | The sign installed in advance of a curve when one is required, recommended or allowed, unless another sign below is recommended or allowed. |
| Turn (W1-1) | Should be used instead of a Curve sign before a curve with an advisory speed of 30 mph or less. |
| Reverse Turn (W1-3) / Reverse Curve (W1-4) | Should be used where two changes in alignment in opposite directions are separated by less than 600 feet, instead of multiple Turn or Curve signs. |
| Winding Road (W1-5) | May be used where there are three or more changes in alignment, each separated by less than 600 feet. A NEXT XX MILES plaque may go below it. |
| Hairpin Curve (W1-11) | May be used where the curve changes direction by 135 degrees or more. |
| 270-degree Loop (W1-15) | May be used where the road changes direction by about 270 degrees, such as a cloverleaf interchange ramp. |
| Combination curve and intersection (W1-10 series) | May be used where a side road or cross road meets the road within or right next to a turn or curve. |
From the Manual on Uniform Traffic Control Devices (MUTCD), 11th Edition with Revision 1, Sections 2C.07 and 2C.09, read November 4, 2026. Driving curves after dark? See our night driving tips.
Chevrons and large arrows
Chevron Alignment (W1-8): gives extra emphasis and guidance through a curve. The MUTCD says it is a vertical rectangle with no border, installed on the outside of a turn or curve, in line with and at about a right angle to approaching traffic, at least 4 feet high. Chevrons may be used instead of, or in addition to, standard delineators.
Spacing: the MUTCD's typical spacing runs from about 40 feet apart on curves with an advisory speed of 15 mph or less to about 200 feet apart where the advisory speed is more than 60 mph.
Not for obstructions: chevrons are not used to mark obstructions such as the start of a guardrail (object markers do that), and chevrons pointing right are not used in the central island of a roundabout or a neighborhood traffic circle.
One-Direction Large Arrow (W1-6): a horizontal rectangle with an arrow pointing left or right, installed on the outside of a turn or curve. It may be used to emphasize an abrupt turn, or as a supplement or alternative to chevrons or delineators where site conditions limit how many can be seen, or where fewer can be installed than the spacing calls for.
From the Manual on Uniform Traffic Control Devices (MUTCD), 11th Edition with Revision 1, Sections 2C.08 and 2C.10 and Table 2C-5, read November 4, 2026.
Advisory speed plaques
What it is: the Advisory Speed (W13-1P) plaque may be used to supplement an advance warning sign to show the advisory speed for a condition. It is only used to supplement a warning sign, never on its own.
How the speed is set: the MUTCD says the speed shown is a multiple of 5 mph and, except in emergencies or when the condition is temporary, the plaque is not installed until the advisory speed has been set by an engineering study.
When it is used on curves: based on the difference between the curve's advisory speed and the speed limit (or the 85th-percentile speed) on the approach: optional at 5 mph, recommended at 10 mph, and required at 15 mph or more.
Truck Rollover (W1-13): may be added after a curve warning sign to warn drivers of trucks, tankers and recreational vehicles. It must be accompanied by an Advisory Speed plaque showing the recommended speed for vehicles with a higher center of gravity. The curved arrow shows the direction of the curve; the truck tips the opposite way.
From the Manual on Uniform Traffic Control Devices (MUTCD), 11th Edition with Revision 1, Sections 2C.11 and 2C.59 and Table 2C-6, read November 4, 2026.
When curve signs are used
The MUTCD first decides whether curve devices are needed: they are required on freeways and expressways at every traffic level, and the need on arterials and collectors depends on daily traffic and pavement markings. Where devices are needed, the difference between the curve's advisory speed and the approach speed sets which ones:
| Speed difference | Devices for the curve |
|---|---|
| 5 mph | Pavement markings or an advance curve warning sign on paved roads; an advance warning sign on unpaved roads. |
| 10 mph | Advance curve warning sign. |
| 15 mph | Delineators and an advance curve warning sign. |
| 20 mph or more | Chevrons and an advance curve warning sign. |
From the Manual on Uniform Traffic Control Devices (MUTCD), 11th Edition with Revision 1, Section 2C.06 and Table 2C-4, read November 4, 2026. Curve devices may be left off where the approach speed limit is 20 mph or less, or on urban streets carrying 1,000 vehicles a day or fewer.
Hill signs
The Hill (W7-1) sign should be used before a downgrade where the length, percent of grade, curves or other features call for special care. The MUTCD says a Hill sign with a grade plaque (or the W7-1a sign alone) should be installed before downgrades like these:
| Grade | Longer than |
|---|---|
| 5% | 3,000 feet |
| 6% | 2,000 feet |
| 7% | 1,000 feet |
| 8% | 750 feet |
| 9% | 500 feet |
From the Manual on Uniform Traffic Control Devices (MUTCD), 11th Edition with Revision 1, Sections 2C.14, 2C.16 and 2C.64, read November 4, 2026. They should also be installed for steeper grades or where crash experience and field observations show a need. A USE LOW GEAR or TRUCKS USE LOWER GEAR plaque may be added where downshifting as well as braking might be advisable, and on longer grades distance plaques at about 1-mile intervals should be considered. A HILL BLOCKS VIEW (W7-6) sign may be used before a hilltop where you cannot see far enough ahead to stop at the posted speed limit.
Keep your tires and brakes ready for curves and hills
The Works® at Ford of Peoria includes a synthetic blend oil change, tire rotation and pressure check, brake inspection, Multi-Point Inspection, fluid top-off, battery test, and a filter, belts and hoses check.
Schedule service online and see our service specials first. Ford of Peoria is at 2211 W. Pioneer Pkwy. in Peoria. Get directions.
Ford of Peoria service hours
| Days | Hours |
|---|---|
| Mon-Fri | 7 a.m.-5:30 p.m. |
| Sat | 8 a.m.-noon |
| Sun | closed |
From Ford of Peoria's website, November 4, 2026. Holiday hours can differ.
Curve and hill warning sign FAQ
What does a Curve sign mean?
The yellow Curve (W1-2) sign warns of a curve in the road ahead. Under the MUTCD, when a horizontal alignment sign is called for, the sign installed in advance of the curve is a Curve sign unless another sign in that section is recommended or allowed.
What is the difference between a Turn sign and a Curve sign?
The MUTCD says a Turn (W1-1) sign should be used instead of a Curve (W1-2) sign in advance of a curve that has an advisory speed of 30 mph or less.
What does a Winding Road sign mean?
The Winding Road (W1-5) sign may be used where there are three or more changes in alignment, each separated by less than 600 feet of straight road. A NEXT XX MILES plaque may go below it where the curves continue for a set distance.
What do the black and yellow chevron signs on a curve mean?
Chevron Alignment (W1-8) signs are installed on the outside of a turn or curve to give extra emphasis and guidance through the change in direction. The MUTCD says they are vertical rectangles with no border, mounted at least 4 feet high.
What does the speed plaque with a curve sign mean?
It is an Advisory Speed (W13-1P) plaque showing the advisory speed for the curve. The MUTCD says the speed shown is a multiple of 5 mph, and except in emergencies or for temporary conditions, it is set by an engineering study.
What does a Hill sign mean?
The Hill (W7-1) sign warns of a downgrade ahead where the length, percent of grade, curves or other features call for special care. On the downgrades the MUTCD lists (see the table above), it should be paired with a supplemental grade plaque (or the W7-1a sign used), and a USE LOW GEAR plaque may be added where downshifting as well as braking might be advisable.
What does HILL BLOCKS VIEW mean?
The HILL BLOCKS VIEW (W7-6) sign may be used on the approach to a hilltop where you cannot see far enough ahead to stop at the posted speed limit. The MUTCD says it should be paired with an Advisory Speed plaque showing the recommended speed over the hillcrest.
What does The Works at Ford of Peoria include?
The Works® at Ford of Peoria includes a synthetic blend oil change, tire rotation and pressure check, brake inspection, Multi-Point Inspection, fluid top-off, battery test, and a filter, belts and hoses check.
Book a routine checkup
Book The Works, which includes a brake inspection, tire rotation and pressure check, and battery test, at Ford of Peoria.
Sources
Sign descriptions are from the Federal Highway Administration's Manual on Uniform Traffic Control Devices, 11th Edition with Revision 1 (Revision 1 dated December 2025), read November 4, 2026. This page is a plain-language summary of national standards, not legal advice; state law sets the rules of the road where you drive. Service details, address and hours are from Ford of Peoria's own website, checked the same day. Photo is illustrative.
- Manual on Uniform Traffic Control Devices (MUTCD), 11th Edition with Revision 1 (Sections 2C.02, 2C.05-2C.11, 2C.14, 2C.16, 2C.59, 2C.64; Tables 2C-4, 2C-5 and 2C-6), Federal Highway Administration, Revision 1 dated December 2025 (PDF updated February 12, 2026), read November 4, 2026
- General service: The Works, Ford of Peoria, November 4, 2026
- Address and service hours (structured data), Ford of Peoria, November 4, 2026