Semi-Truck Blind Spots: A Visual Guide to Staying Safe on I-70

If you've ever driven I-70 between St. Louis and Kansas City, you've spent plenty of time sharing the road with semi-trucks. Missouri's main east-west corridor is one of the busiest truck routes in the nation — and also one of the most dangerous for passenger vehicles.

The key to surviving? Understanding where truck blind spots are and how to stay out of them.

The "No-Zone": Where Trucks Can't See You

The Federal Motor Carrier Safety Administration coined the term "No-Zone" to describe the areas around a semi-truck where the driver has limited or no visibility. These aren't small blind spots like the ones in your car. A semi-truck's No-Zones are massive — and being in them can be deadly.

The Four Major Blind Spots

1. Directly in Front (20 feet)

A semi-truck sits 4–6 feet above the road. The driver cannot see anything within approximately 20 feet directly in front of their bumper. If you merge in front of a truck and don't leave enough space, you're invisible.

Danger on I-70: Traffic frequently slows between St. Louis and St. Charles. Drivers who cut in front of trucks to change lanes during these slowdowns are putting themselves at extreme risk. The truck driver physically cannot see you if you're too close.

2. Directly Behind (200 feet)

The driver can't see anything within roughly 200 feet behind the trailer. If you're tailgating a truck, you're not only invisible — you're also driving in a zone where the truck may brake suddenly without you having time to react.

3. The Right Side (Two lanes wide)

This is the largest blind spot. A truck driver cannot see vehicles that are next to the right side of their trailer — an area that extends approximately two lanes to the right. This is especially dangerous because right turns require the truck to swing wide, potentially crushing anything in that zone.

4. The Left Side (One lane)

The left blind spot is smaller than the right — about one lane wide — but it still exists. If you're hanging out in the lane to the truck's left and you're not well past the cab, the driver may not see you.

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I-70 Specific Dangers

The St. Louis to St. Charles Corridor

This stretch of I-70 is under constant construction and carries extremely heavy truck traffic. The combination of narrowed lanes, concrete barriers, and frequent merge points creates situations where passenger vehicles are forced into truck blind spots.

Highway 40/64 Interchange

The interchange where I-64 meets I-70 near downtown St. Louis is one of the most congested and dangerous interchanges in the state. Multiple lanes merge, trucks are trying to maintain speed, and passenger vehicles dart between them — often into No-Zones.

The Columbia and Kingdom City Rest Areas

These areas see heavy truck traffic entering and exiting the highway. Merging back onto I-70 alongside accelerating semi-trucks requires extra caution.

Rural I-70 Between Exits

In the rural stretches, truck speeds are high and passing opportunities are limited. Drivers who linger in truck blind spots while attempting to pass are at significant risk.

How to Share the Road Safely

Passing a Semi-Truck

1. Approach from the left lane — the left blind spot is smaller
2. Signal early and wait until you can see the truck's headlights in your rearview mirror before merging back
3. Pass quickly — don't linger in the blind spot
4. Maintain your speed while passing — don't slow down midway through
5. Never pass on the right unless absolutely necessary — the right blind spot is enormous

Being Passed by a Semi-Truck

1. Maintain your speed — don't speed up or slow down
2. Stay in your lane — let the truck complete the pass
3. Don't move to the right to "give room" — you may end up in the right blind spot of another truck

Following a Semi-Truck

1. Stay back at least 20–25 car lengths — this gives you time to react if the truck brakes suddenly
2. If you can't see the truck's mirrors, back off — you're too close
3. Never draft behind a truck — it's not worth the fuel savings

Merging onto I-70 Near Trucks

1. Match highway speed before merging — don't force a truck to brake
2. Check mirrors for trucks in the right lane before merging
3. Don't assume the truck can or will move over — they may have another vehicle on their left

What to Do If a Truck Is Following Too Closely

If a semi-truck is tailgating you:

1. Don't brake-check — the truck cannot stop as quickly as you can
2. Signal and move to the right lane when safe
3. Let the truck pass — it's not worth the risk
4. If you can't move over, maintain steady speed and increase following distance from the vehicle in front of you, giving yourself more reaction time

If You've Been in a Truck Accident

Truck blind spot accidents are often severe because the truck driver may not even realize they've hit a vehicle until it's too late. If you've been injured in a truck accident on I-70 or anywhere in Missouri:

• Get medical attention immediately
• Request the truck's electronic logging device data — this must be preserved quickly
• Document the accident scene thoroughly
• Contact an attorney experienced in truck accident cases — these are fundamentally different from car accidents

Call 314-721-3040 for a free consultation.

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