Why Do Some Trucks Pull Two Smaller Trailers Instead of One Big Trailer?

Have you seen big trucks on the road with two smaller trailers hooked up together? Let’s find out why trucking companies use them.

What Are Double Trailers?

Double trailers (also called tandem trailers) are when a truck pulls two shorter trailers instead of one long one. These trucks use a special part called a converter dolly to hook the trailers together.

Learn more about tractor units for semi-trailers

Why Companies Choose Two Trailers Instead of One

1. They Can Carry More Weight Legally

Trucks must follow weight laws. With more axles and wheels, trucks can carry heavier loads without breaking rules.

Key fact: Trucks with two trailers (like B-trains or A/C-trains) can legally carry up to 46,500 kg (102,500 lbs) across 8 axles.

2. It’s More Efficient for Business

Double trailers help companies save money and time:

• Move more goods with each trip (2-3 times more cargo)
• Drop off one trailer and keep going with the other
• Lower costs per mile of driving

Check out dump trucks that use similar weight distribution principles

3. Better for City Driving and Tight Spaces

Two shorter trailers can turn corners better than one long trailer. This helps when:

• Driving in cities with tight turns
• Backing up to loading docks
• Going through warehouse yards

4. Helps With Loading and Unloading

Companies like FedEx, UPS, and Old Dominion use double trailers because:

• Trailers can be loaded while the truck is away
• Drivers don’t wait as long at shipping terminals
• One trailer can be dropped off while the other keeps going

5. Better Tire Wear and Safety

Dual wheels on trailers help:

• Spread weight more evenly
• Make trucks more stable
• Reduce tire blowouts

See how material handling vehicles use similar stability features

Comparing One Big Trailer vs. Two Smaller Trailers

Feature	One Big Trailer	Two Smaller Trailers
Max Legal Weight	Limited by fewer axles	Up to 46,500 kg across 8 axles
Productivity	Lower cargo capacity	2-3x more cargo per trip
Turning Ability	Harder to turn	Better for tight spaces
Dropping Loads	Must unload everything at once	Can drop one trailer and keep going
Cost	Higher per load	Lower operating cost per mile

Who Uses Double Trailers?

• Shipping companies like FedEx, UPS, Old Dominion
• Long-haul truckers going between big cities
• Delivery services with many stops

Are There Any Downsides?

• Drivers need more training to handle double trailers
• Some states have special rules about where these trucks can go
• The converter dolly needs extra care and checks

Helpful Facts About Double Trailers

• They are also called LCVs (Long Combination Vehicles)
• The small trailers are often 28 feet long
• The special link between trailers is called a converter dolly
• These trucks need more tire checks and maintenance

Explore semi-trailer options for various hauling needs

Conclusion

Trucking companies use two smaller trailers instead of one big one because it helps them:

1. Stay within legal weight limits
2. Carry more cargo each trip
3. Drive better in tight spaces
4. Save time and money
5. Be more flexible with deliveries

This smart way of moving goods helps keep costs down for companies and gets products to stores faster.