How to Cross Railroad Tracks and Drive Mountain Grades - Step-by-Step Tutorial

Railroad crossings and mountain grades require specific techniques for safe commercial vehicle operation. This tutorial covers the proper procedures for crossing tracks safely and using the snub braking technique on downgrades—both commonly tested on the CDL exam.

Difficulty Level: Intermediate
Time Required: 15 minutes to understand concepts
Prerequisites: Basic commercial vehicle operation knowledge

Part 1: Railroad Crossing Procedures

Step 1: Identify the Crossing Type

Passive Crossing (No Devices)

• No flashing lights, bells, or gates
• Only cross-buck sign or pavement markings
• YOU must decide if safe to cross

Active Crossing (Has Devices)

• Flashing red lights and/or bells
• May have gates
• Devices tell you when to stop

Step 2: Approach the Crossing

1. Slow down as you approach
2. Look for the round advance warning sign (black-on-yellow)
3. Watch for pavement markings (X with RR)
4. Turn off radio/distractions—listen for trains
5. Check both directions for trains

Remember: You cannot always hear a train coming. Don't rely on your hearing alone.

Step 3: Determine if You Must Stop

Mandatory stop required for:

• Vehicles carrying hazardous materials
• Buses carrying passengers
• When required by law
• When visibility is limited
• When active devices are activated

Step 4: Stop Properly

Stopping distance from tracks:

Stopping procedure:

1. Check mirrors for traffic behind
2. Slow gradually (don't brake suddenly)
3. Use pullout lane if available
4. Turn on 4-way flashers
5. Stop within 15-50 feet of nearest rail

Step 5: Check Before Crossing

Before proceeding:

• Look LEFT
• Look RIGHT
• Look LEFT again
• Check for second train if double tracks
• Ensure you can clear ALL tracks completely

Step 6: Cross Safely

Crossing times to remember:

Part 2: Mountain Driving - Downgrade Procedure

Step 1: Prepare Before the Downgrade

Check these factors to select safe speed:

1. Total weight (vehicle + cargo)
2. Length of grade
3. Steepness of grade
4. Road conditions
5. Weather

Obey posted signs:

• Speed limits
• "Maximum Safe Speed" signs
• Grade percentage and length warnings

Step 2: Select Proper Gear BEFORE Starting Down

This is critical—you must shift before the descent.

Gear selection guide:

Why modern trucks need lower gears: Less friction and air drag means less natural slowing.

Step 3: Use Engine Braking as Primary Control

Engine braking is most effective when:

• Engine is near governed RPMs
• Transmission is in low gear

Your brakes are only a SUPPLEMENT to engine braking.

Step 4: Apply the Snub Braking Technique

This is the proper braking method for long, steep downgrades:

The Snub Braking Cycle:

1. Let speed build to your "safe speed"
         ↓
2. Apply brakes FIRMLY (feel definite slowdown)
         ↓
3. Slow to 5 mph BELOW safe speed
         ↓
4. Release brakes (application ~3 seconds)
         ↓
5. Let speed return to safe speed
         ↓
6. Repeat until end of grade

Step 5: Example of Snub Braking

If your safe speed is 40 mph:

Key: Each brake application lasts about 3 seconds, then release.

What NOT to Do on Downgrades

Mistake 1: Riding the brakes Continuous light pressure overheats brakes, causing fade and failure. Use snub braking instead.

Mistake 2: Waiting to downshift Once speed builds up, you cannot shift to a lower gear. Select gear BEFORE the descent.

Mistake 3: Relying only on brakes Engine braking is your primary control. Brakes supplement the engine.

Mistake 4: Ignoring brake fade If you need more pressure for the same stopping power, your brakes are fading. Find a safe place to stop and let them cool.

Handling Emergencies

If Stuck on Railroad Tracks

1. GET OUT immediately
2. Move away from tracks
3. Find emergency number on signal post
4. Call 911
5. Provide DOT crossing number and location

If Brakes Fail on Downgrade

1. Pump brakes to build pressure
2. Downshift if possible
3. Use escape ramp (know locations!)
4. Look for upgrade or soft surface
5. As last resort, rub against guardrail to slow

Escape ramps save lives. Know their locations on your route.

Common Mistakes to Avoid

Railroad Mistake: Shifting on tracks Never shift gears while crossing—you could stall and get stuck.

Railroad Mistake: Racing a train You cannot accurately judge train speed. Never try to beat a train.

Mountain Mistake: Using same gear down as up (modern trucks) Modern trucks need LOWER gears going down due to less friction and air drag.

Mountain Mistake: Continuous braking Causes brake fade. Use snub braking—firm pressure, then release.

Frequently Asked Questions

Q: How far from tracks should I stop?

A: Between 15 and 50 feet from the nearest rail.

Q: How long to clear a double track?

A: More than 15 seconds for a typical tractor-trailer.

Q: When do I shift for a downgrade?

A: Before starting down. Once speed builds, you can't downshift.

Q: What is snub braking?

A: Firm braking to slow 5 mph below safe speed (~3 seconds), then release. Repeat as needed.

Q: What gear for downhill in modern trucks?

A: Usually lower than the gear needed to climb the same hill.

Q: What causes brake fade?

A: Excessive heat from continuous braking or overuse instead of engine braking.

Quick Reference

Railroad Crossing

• Stop 15-50 feet from tracks
• Single track: 14 seconds to clear
• Double track: 15+ seconds to clear
• Never shift on tracks

Mountain Driving

• Shift to low gear BEFORE descent
• Engine braking = primary control
• Snub braking: slow 5 mph below safe speed
• Each application: ~3 seconds

Next Steps

1. Memorize stopping distances: 15-50 feet
2. Know track clearing times: 14/15+ seconds
3. Practice identifying when to use snub braking
4. Remember: gear selection happens BEFORE the hill

Ready to test your knowledge? Start practicing with our Railroad and Mountain Driving questions.