What Is a Bobtail Truck?
A bobtail truck is a semi-truck tractor driving without a trailer attached. When a driver is “bobtailing,” they are operating the cab-only portion of what is normally a tractor-trailer combination. Bobtailing is common when repositioning between loads, returning to a terminal after dropping a trailer, or picking up a new trailer. While it seems like driving should be easier without 40,000+ lbs of freight behind you, bobtailing is actually more dangerous than driving with a loaded trailer due to braking and handling differences.
O Trucking Editorial Team
Trucking Industry Experts
Fact-Checked by O Trucking Dispatch Team
5+ years dispatching owner-operators and managing load planning to minimize non-revenue bobtail and deadhead miles
This article was written by the O Trucking editorial team with 9+ years of combined trucking industry experience. Learn more about us.
O TruckingBobtail Truck: Definition & Safety Guide (2026)
What Is a Bobtail Truck?
A bobtail truck is a semi-truck tractor — the front portion of an 18-wheeler — operating on the road without a trailer connected to it. The driver is “bobtailing” whenever the tractor's fifth wheel is empty and no trailer is hooked up. This is a normal part of trucking operations that happens in several situations:
- Repositioning between loads — After dropping off a loaded trailer, the driver may need to drive to a different location to pick up the next trailer or load
- Returning to a terminal — After delivering a load and dropping the trailer at the consignee, the driver drives back to the carrier's terminal bobtail
- Picking up a new trailer — Driving to a yard, shipper, or drop lot to hook up a pre-loaded trailer
- Personal use — Some owner-operators use their tractor for personal errands when not on dispatch (requires proper insurance coverage)
- Maintenance — Driving the tractor to a repair shop, truck wash, or inspection station without a trailer
A typical bobtail truck weighs between 10,000 and 25,000 pounds depending on the tractor model. A day cab tractor bobtails at roughly 15,000-17,000 lbs, while a sleeper cab bobtails at 17,000-21,000 lbs. For comparison, the same tractor pulling a loaded trailer weighs up to 80,000 lbs.
Bobtail vs Normal Operations
Bobtail
Tractor only, no trailer. 10,000-25,000 lbs.
Deadhead
Tractor + empty trailer. 25,000-35,000 lbs.
Loaded
Tractor + loaded trailer. Up to 80,000 lbs.
Why Is Bobtailing Dangerous?
Counterintuitively, driving a lighter truck without a trailer is more dangerous than driving a loaded 80,000 lb rig. The reason comes down to physics and brake system design:
Longer braking distance — A semi-truck's brake system is engineered to stop up to 80,000 lbs. Without the trailer's weight pressing the rear tires into the pavement, the rear brakes have drastically reduced traction. Braking distance on a bobtail can be 40% or more longer than with a loaded trailer, especially on wet roads.
Rear wheel lockup — Without trailer weight, the rear axle brakes can easily overpower the available traction, causing the rear wheels to lock and the truck to skid. This is especially dangerous on wet, icy, or loose surfaces. Anti-lock braking systems (ABS) help but do not eliminate the problem.
Crosswind instability — A loaded trailer acts as an anchor that stabilizes the truck in crosswinds. Without a trailer, a bobtail truck has a high center of gravity relative to its contact patch with the road, making it more susceptible to being pushed by strong crosswinds — particularly on bridges and overpasses.
Rough ride quality — The tractor's suspension is designed for the combined weight of tractor and trailer. Without trailer weight, the ride is stiffer and bouncier, which can cause driver fatigue and make it harder to maintain precise steering input.
For a deep dive on bobtail safety with specific driving techniques and accident prevention strategies, see our complete bobtail safety guide.
Increase Following Distance When Bobtailing
Bobtail vs Deadhead: What Is the Difference?
Bobtailing and deadheading are both non-revenue driving situations, but they are fundamentally different:
| Factor | Bobtail | Deadhead |
|---|---|---|
| Configuration | Tractor only, no trailer | Tractor + empty trailer |
| Weight | 10,000-25,000 lbs | 25,000-35,000 lbs |
| Braking safety | More dangerous | Slightly dangerous |
| Fuel economy | Better (5-7 MPG) | Worse (4-6 MPG) |
| Revenue | $0 per mile | $0 per mile |
| Maneuverability | Excellent | Same as loaded |
For a comprehensive comparison including when each situation occurs and how to minimize both, see our bobtail vs deadhead guide.
Why Is It Called a “Bobtail” Truck?
The word “bobtail” predates trucking by centuries. It originally referred to an animal — typically a horse or cat — whose tail had been docked (cut short). A horse with a bobbed tail was called a “bobtail horse.” The most famous cultural reference is the 1857 song “Jingle Bells” by James Lord Pierpont, which contains the line “bells on bobtail ring” — referring to a bobtail horse pulling a sleigh.
When applied to trucking, the connection is visual: a semi-truck without its trailer looks like it has been “cut short” — it appears to be missing its back end, just like an animal with a docked tail. The term has been used in the trucking industry since at least the 1950s and is universally understood by truckers across North America. For the full history, see our bobtail name origin guide.
Bobtail Insurance
Standard trucking liability insurance typically covers your truck only while it is under dispatch — meaning actively carrying a load or en route to pick one up. When you are bobtailing for personal use or between dispatches, you may not be covered. That is where bobtail insurance comes in.
There are two types of coverage for off-dispatch driving:
Bobtail insurance — Covers the truck when operating without a trailer and not under dispatch. Typically costs $30-$60/month. Most relevant for independent owner-operators with their own authority.
Non-trucking liability (NTL) — Covers the truck during any non-business use, including personal errands and commuting. Typically costs $35-$65/month. Most relevant for owner-operators leased onto a carrier who provides primary liability under dispatch.
The distinction matters because using the wrong coverage type can result in a denied claim. For a full breakdown of bobtail insurance costs, coverage, and requirements, see our bobtail insurance guide and our bobtail insurance glossary entry.
Confirm Your Coverage Gaps Before You Need Them
Bobtail Truck Weight and Regulations
Even without a trailer, a bobtail truck is still a commercial motor vehicle (CMV) subject to federal and state regulations:
Weight — Bobtail trucks typically weigh 10,000-25,000 lbs. Day cabs bobtail at 15,000-17,000 lbs; sleeper cabs at 17,000-21,000 lbs. The weight depends on the tractor model, fuel tank capacity, and equipment.
Weigh stations — In most states, bobtail trucks must stop at open weigh stations. The truck is still a CMV with a GVWR over 10,001 lbs. Some states have exemptions for bobtail trucks below certain thresholds — check state-specific rules.
CDL requirement — You still need a CDL to drive a bobtail truck because the vehicle's GVWR exceeds 26,001 lbs (the CDL threshold). The CDL requirement applies to the vehicle, not to what it is hauling.
Hours of Service — HOS rules apply when bobtailing if you are operating as a CMV driver. However, if you are using the truck for purely personal use (personal conveyance), you may use the personal conveyance exemption.
For a complete breakdown of bobtail weight by model and regulations by state, see our bobtail weight and regulations guide.
How to Reduce Bobtail Miles
Every bobtail mile is a mile driven with zero revenue, burning fuel and adding wear to the truck with nothing to show for it. Reducing bobtail miles is one of the most effective ways to increase your profitability. Here are proven strategies:
Plan your next load before you drop — The best time to find your next load is before you deliver your current one. If you know where you will be dropping, start looking for pickup opportunities near that location. A good dispatcher does this automatically.
Use relay and drop-and-hook loads — Drop-and-hook operations let you drop one trailer and immediately hook another at the same location, eliminating bobtail miles entirely. Seek out shippers and receivers that operate on a drop-and-hook basis.
Build dedicated lanes — Regular lanes between consistent shippers reduce repositioning. When you run the same route repeatedly, you can arrange pickups near your delivery points. See our dedicated lanes guide.
Accept nearby short loads over distant high-paying loads — A $500 load 20 miles from your drop point may be more profitable than a $1,200 load 150 miles away after factoring in the bobtail fuel cost and time.
For a complete strategy guide with calculations, see our reducing bobtail miles guide.
How Our Dispatch Team Minimizes Your Bobtail Miles
At O Trucking LLC, reducing non-revenue miles is a core part of our dispatch strategy:
Pre-planned next loads
Before you deliver your current load, we are already finding your next pickup near your drop location. Our goal is to have your next load confirmed before you even unhook your current trailer — minimizing or eliminating bobtail repositioning.
Load chaining to minimize empty miles
We plan your loads in sequence so each delivery point is near the next pickup point. When bobtail miles are unavoidable, we keep them to an absolute minimum — rarely more than 20-30 miles between drop and pickup.
Backhaul sourcing
When a driver delivers to an area with limited outbound freight, we source backhaul loads — even at slightly lower rates — because earning something on the return trip is always better than bobtailing home at $0 per mile.
Related Resources
Bobtail Truck Guide Collection
Bobtail vs Deadhead
What is the difference?
Bobtail Safety
Braking, handling & safety tips
Bobtail Insurance
Cost, coverage & requirements
Name Origin
Why is it called a bobtail?
Reduce Bobtail Miles
Maximize revenue, minimize empty
Weight & Regulations
Weigh stations, CDL & rules
Bobtail Fuel Economy
MPG and cost per mile without trailer
Bobtail Truck FAQ
Common questions about bobtail trucks, safety, insurance, weight, and regulations
What is a bobtail truck?
A bobtail truck is a semi-truck tractor driving without a trailer attached. The term 'bobtailing' refers to operating the cab-only portion of what is normally a tractor-trailer combination. Drivers bobtail when repositioning between loads, returning to a terminal after dropping a trailer, or picking up a new trailer at a different location. A bobtail truck typically weighs between 10,000 and 25,000 pounds depending on the tractor model and configuration.
Why is bobtailing dangerous?
Bobtailing is dangerous primarily because of braking issues. A semi-truck's braking system is engineered to stop the combined weight of the tractor plus a loaded trailer (up to 80,000 lbs). Without the trailer's weight pressing down on the rear axles, the rear brakes have significantly less traction. This means the rear wheels can lock up more easily, especially on wet or icy roads, leading to longer stopping distances, jackknife-like skids, and reduced steering control. Bobtail trucks also handle differently in crosswinds because there is no trailer to stabilize the rear of the vehicle.
What is the difference between bobtailing and deadheading?
Bobtailing means driving a semi-truck without any trailer attached — just the tractor cab by itself. Deadheading means driving with a trailer attached, but the trailer is empty (no freight). Both represent non-revenue miles, but they are different situations with different handling characteristics. Bobtailing is generally more dangerous than deadheading because an empty trailer still provides some weight and stability to the rear axles. Deadheading is less fuel-efficient than loaded driving because you are hauling the weight of an empty trailer without earning revenue on it.
Why is it called a bobtail truck?
The term 'bobtail' comes from the practice of docking (cutting short) an animal's tail — a horse or cat with a shortened tail was called 'bobtailed.' A semi-truck without its trailer looks like it has been cut short, like an animal with a bobbed tail. The term is also referenced in the popular Christmas song 'Jingle Bells' with the line 'bells on bobtail ring,' referring to a horse with a docked tail pulling a sleigh. In trucking, the term has been used since at least the mid-20th century.
Do you need special insurance for bobtailing?
Yes. Standard trucking liability insurance typically only covers the truck when it is under dispatch (carrying a load or en route to pick one up). When you are bobtailing for personal use or between dispatches, you need either bobtail insurance or non-trucking liability (NTL) insurance to cover accidents. The type you need depends on your operating situation — owner-operators leased to a carrier typically need NTL, while independent owner-operators with their own authority typically need bobtail insurance. See our bobtail insurance guide for the full breakdown.
Do bobtail trucks have to stop at weigh stations?
Requirements vary by state. In most states, commercial motor vehicles (CMVs) must stop at open weigh stations regardless of whether they are pulling a trailer. Since a bobtail truck is still a CMV with a GVWR over 10,001 lbs, it is generally subject to weigh station requirements. However, some states exempt bobtail trucks below certain weight thresholds or when not carrying cargo. The safest practice is to always stop at open weigh stations unless you have a bypass device (PrePass or Drivewyze) that clears you to proceed.
How much does a bobtail truck weigh?
A bobtail truck (semi-truck tractor without a trailer) typically weighs between 10,000 and 25,000 pounds depending on the model, configuration, and fuel load. Day cab tractors weigh 15,000-17,000 lbs. Sleeper cab tractors weigh 17,000-21,000 lbs. The wide range accounts for different fuel tank sizes (100-300 gallons), fifth wheel types, and optional equipment. Even though a bobtail is relatively light for a commercial vehicle, it is still heavy enough to cause severe damage in an accident.
Want a Dispatch Team That Minimizes Bobtail Miles?
Our dispatchers plan your loads in sequence to eliminate unnecessary bobtail repositioning. We find your next pickup before you drop your current load — keeping your revenue per mile high and your empty miles low.