Due to the unique size, weight, and handling of commercial vehicles, truck drivers must pay close attention to a variety of highway signs designed specifically for them. These truck-specific signs are essential for safe navigation. Ignoring or misunderstanding them can lead to violations, vehicle damage, or hazardous situations.

There are a wide variety of signs that truck drivers need to know, including:

• Weight limit and load restriction signs.
• Height clearance and low bridge signs.
• Truck route and restricted access signs.
• Runaway truck ramps.
• Steep grade and brake check signs.
• Weigh station and inspection station signs.
• Hazardous material route signs.
• Toll road and truck-specific toll signs.

In this post, we’ll walk through the key highway signs every driver should know, and what they mean for your time on the road.

Weight Limit and Load Restriction Signs

Weight limit and load restriction signs protect infrastructure and help keep everyone on the road safe. Here are a few common signs and what they mean.

Bridge Weight Limit __ Tons

If your vehicle exceeds the limit, you must take an alternate route.

No Trucks Over __ lbs GVW

Indicates that vehicles that exceed this specified gross vehicle weight (GVW) are not allowed on the indicated road.

Ignoring these signs can have serious consequences. Overweight trucks can damage roads and bridges, leading to costly repairs. Violations can also result in fines or being stopped and rerouted by law enforcement. Understanding and respecting weight limit signs helps keep the roads safe.

Height Restriction Signs for Drivers

Low clearance and height restriction signs are designed to prevent one of the most avoidable and costly accidents on the road: a truck getting stuck under a bridge or overpass. These signs warn drivers of the maximum vehicle height allowed on a particular stretch of road. Examples of low clearance and height restriction signs include the following.

Clearance 12’-6”

If your truck is taller than the posted height, you must find an alternate route. Sometimes, signs like this will just have arrows with feet and inch measurements (without the word “clearance”).

Low Bridge Ahead

Provides advance notice of a low clearance ahead, often providing the specific height allowed. This gives drivers time to reroute.

Failing to heed these warnings can lead to serious consequences. A truck that hits or becomes lodged under a low overpass can cause significant vehicle damage, major traffic disruptions, and expensive fines. This issue is especially common in older urban areas, particularly on the East Coast, where historic bridges often have low clearances. Know your truck’s height and watch for clearance signs to avoid dangerous or expensive accidents.

Truck Route and No-Truck Signs

Truck route and no-truck signs keep commercial vehicles on roads that can safely handle their size, weight, and turning radius. These signs guide drivers toward approved routes and away from areas where large vehicles could pose a risk. Here are a few examples of these types of signs.

Truck Route

Directs trucks to approved roads designed for heavy vehicles. These sometimes include arrows or highway signs to help indicate the correct route.

No Trucks Except Local Deliveries

Prohibits through traffic but allows local drop-offs and pickups.

Ignoring these signs can land you in tricky or dangerous situations. Violations can also lead to fines or citations. Following posted truck routes helps protect your equipment, ensures smoother travel, and keeps you in compliance.

Runaway Truck Ramp Signs

Runaway truck ramp signs are often found on steep downhill grades. They indicate the location of these ramps, which are safety features designed to stop out-of-control vehicles using sand, gravel, or steep upward inclines to slow vehicles. 

Runaway Truck Ramp 1 Mile

Indicates the distance until there is a runaway truck ramp.

Runaway Truck Ramp or Truck Escape Ramp

Lets drivers know that an escape ramp is coming up very soon, often indicated by an arrow, so they can use the ramp if needed.

Knowing where runaway truck ramps are, and using them when needed, can be the difference between a safe stop and a serious accident.

Steep Grade and Brake Check Signs

Brake check and steep grade warning signs help truck drivers safely navigate long or steep downhill stretches. These signs alert drivers to upcoming conditions so they can use lower gears and slower speeds as needed.

Steep Grade Next 5 Miles

Warns drivers of a sustained, steep descent, and it lets them know how long to expect that steep grade to last.

Truck Brake Check Area

Lets drivers know where the next truck brake check area is. A brake check is a designated spot, usually at the top of a steep grade, where drivers are encouraged (or sometimes required) to pull over and check their brakes. 

Ignoring these warnings can be dangerous. Brakes that overheat from constant use may lose effectiveness or fail completely. Additionally, descending in the wrong gear can strain or damage your transmission, leading to delays, costly repairs, or difficult handling.

Weigh Station and Inspection Station Signs

Weigh station and inspection station signs enforce commercial vehicle safety and weight regulations. These signs let truck drivers know when and where they are required to stop so that authorities can verify compliance with legal weight limits and safety standards.

Weigh Station – All Trucks Must Stop When Open

This sign means you must exit the highway and enter the weigh station if it's operating.

Prepass Available – Follow In-Cab Signal

If your vehicle is equipped with a prepass system (like Prepass or Drivewyze), this sign lets you know to follow the instructions on your in-cab prepass system. If you are given the go-ahead, you can bypass the weigh station. Drivers who don’t have a prepass system must stop at the weigh station unless instructed not to.

Failing to stop at a required weigh station can result in fines or citations. It's also possible that law enforcement will pull you over down the road. To stay in compliance and avoid delays, always watch for these signs and follow the instructions carefully.

Hazardous Materials Route Signs

Hazardous materials (HM) signs are essential for protecting public safety and the environment. These signs guide drivers transporting hazardous materials to approved roads and away from restricted or high-risk areas like tunnels, bridges, and densely populated areas. Here are a few examples of HM signs.

HM with Green Circle

Informs drivers that the transportation of hazardous material is allowed on the route. Some signs might also include an arrow for directions for allowed routes.

HM with Red “Not Allowed” Circle

Indicates that drivers are not allowed to bring hazardous materials on the route. Sometimes, cities will use signs with language like “No Hazardous Materials Beyond This Point,” letting you know where hazardous materials are and aren’t allowed.

Ignoring hazmat route signs is a regulatory concern and a serious safety concern. Transporting hazardous materials on unauthorized routes can lead to fines, legal action, and potentially dangerous incidents. Knowing and following these signs is critical for staying compliant and keeping both people and property out of harm’s way.

Toll Signs

Toll road and truck-specific toll signs help commercial drivers navigate toll areas. These signs provide important details like toll rates, lane assignments, and accepted payment methods, which vary from state to state.

Pay Toll 1 Mile

These signs let drivers know that there is an upcoming toll. If you have an electronic toll collection system installed (like E-ZPass), you might be able to bypass toll booths, and your tolls will be deducted from your account. Just make sure your collection system works in the state that you are driving in.

Exact Change or Cash - Change Receipts

These signs indicate which lanes to use if you have exact change and which ones to use if you need change or a receipt.

Failure to pay tolls, using the wrong lane, or using the incorrect payment method can result in violations, delays, or fines. Paying attention to toll signage helps keep traffic flowing and avoids unnecessary penalties.

Stay Safe and Know Your Truck Highway Signs

Understanding and following truck-specific highway signs is essential to staying safe, protecting your rig, and keeping your record clean. Weight limits, height restrictions, toll guidance, hazardous material routes, and more are designed to help you make smart decisions on the road.

Drive with Pride Transport

We know that great drivers are also informed drivers. That’s why we support our team with the tools, training, and respect they deserve. If you’re looking for a carrier that values safety, professionalism, and your success behind the wheel, consider joining our team. We’re committed to helping you navigate every mile with confidence.