If you are towing anything behind a U-Haul, the answer is 55 mph, because that is the maximum speed U-Haul publishes for its own trailers. If you are driving a moving truck without a trailer, no major rental company publishes a maximum at all. Your limit is the posted sign, lowered by state law in the handful of states that treat trucks and towing vehicles differently, and lowered again by common sense once the box is full.
The short answer
People ask this question expecting a single number stamped on the rental contract. There usually is not one. What actually constrains you is a stack of three things, in this order: the posted speed limit on the road you are on, any state statute that sets a lower figure for your vehicle or your towing configuration, and the published guidance from the company you rented from. The engine is almost never the binding constraint, even on trucks that are speed limited.
The one place a clear number does exist is towing. U-Haul states a maximum recommended speed of 55 mph for its trailers, and it repeats that figure on individual equipment pages. Since a huge share of U-Haul rentals involve a tow dolly, an auto transport or a cargo trailer, that is the number most people are actually looking for.
What each company actually says
Here is what is verifiable from the companies' own published material, and where the gaps are. Anything marked as commonly reported is what drivers say, not what the company states.
| Company | Vehicle or situation | Stated limit | Source type |
|---|---|---|---|
| U-Haul | Any U-Haul trailer or tow dolly | 55 mph maximum recommended, and never over the posted limit | Published towing instructions on uhaul.com |
| U-Haul | Auto Transport car trailer | Max recommended speed 55 mph | Equipment specification page |
| U-Haul | 10, 15, 20 and 26 ft trucks, no trailer | No published figure. Guidance is to abide by posted limits | U-Haul help and blog content |
| Penske | Moving and commercial trucks | No published figure. "Never drive faster than the posted speed limit" | Penske driver safety guidance |
| Budget Truck | Moving trucks | No speed clause in the rental terms. Racing and speed contests are prohibited uses | Budget Truck rental terms and conditions |
| Enterprise Truck Rental | Box trucks, vans, pickups | No published speed figure located | Absence of any primary source |
| Any company | Towing anything in California | 55 mph, by statute | California Vehicle Code 22406 |
Two things are worth pulling out of that table. First, the sample U-Haul rental contract that is publicly available does not contain a speed clause at all. The 55 mph towing figure lives in U-Haul's safety and equipment documentation, not in the terms you sign. It is still the company's stated maximum, and ignoring it would be an obvious problem in any dispute about how an accident happened, but it is not accurate to call it a contract term.
Second, Budget's terms do list prohibited uses, and racing or speed contests are among them, alongside the usual bans on driving under the influence and using unpaved surfaces. Rental agreements across the industry work the same way. They do not name a number, they name categories of misuse, and gross misuse can void your damage waiver.
Towing is where the real number lives
A trailer changes the vehicle from a single rigid object into a hinged, two-part system, and that system has a stability threshold. Above a certain speed, small disturbances such as a gust, a lane change or a crown in the road stop damping out and start amplifying. That is trailer sway, and it is the reason every towing guidance document in existence asks you to slow down rather than steer harder.
U-Haul's published answer to that physics is 55 mph, applied uniformly across its trailer range, along with an instruction to reduce your speed further from whatever you would normally drive without a trailer under the same road conditions. Loading matters as much as speed here. Weight biased toward the rear of a trailer moves the combined center of gravity backward and lowers the speed at which sway begins, which is why the loading instructions ask for roughly 60 percent of the cargo weight in the front half.
Are rental trucks speed governed?
Often, yes, but be careful with the numbers you read. Speed limiting on a modern commercial chassis is a software setting in the engine control unit, not a mechanical stop, and fleets configure it per vehicle class and model year. None of the four companies publish a fleet-wide governed speed. The specific figures that circulate in forums, whether 65, 70 or 75 mph, are individual driver reports from individual trucks. Treat them as anecdotes.
What "governed" means in practice is straightforward. Below the threshold the truck behaves normally. As you approach it, the engine stops adding fuel and the truck simply will not accelerate further on level ground, even with the accelerator flat. On a long downhill gravity can still push you past the setting, because a limiter restricts engine output rather than applying the brakes. That is exactly the situation where an overloaded truck gets away from a driver, so a governor is not a substitute for engine braking and early speed control on a descent.
We are not going to explain how to raise or defeat a limiter. It is set for the load rating and brake capacity of that specific chassis, removing it makes the truck less safe for everyone around it, and tampering with a rental vehicle breaches the rental agreement and would likely leave you personally liable for any damage.
State laws that quietly lower your limit
This is the part most renters miss. In a majority of states you may drive a moving truck at the posted limit, but a minority of states set a separate, lower ceiling for heavy vehicles or for anything towing, and it applies whether or not the posted sign says so. Three concrete, statutory examples:
- California. Vehicle Code section 22406 caps any motortruck drawing another vehicle, and any passenger vehicle drawing another vehicle, at 55 mph statewide. If you are towing anything in California, 55 is the law, not a suggestion.
- Michigan. Where the posted limit is above 65 mph, a truck of 10,000 pounds gross weight or more, or any combination towing a trailer, is held to 65 mph on limited access freeways and state trunk line highways.
- Washington. Vehicles over 10,000 pounds gross weight and vehicles in combination are limited to 60 mph, below the 70 mph posted on some interstates.
Other states apply variations of the same idea, often keyed to vehicle weight, road class or trailer type, so a cross-country move can pass through several different rules without a single sign telling you. Before a long trip it is worth checking the states you will cross. Our US speed limits overview and the state-by-state pages behind it are the quickest way to see what the baseline is in each one.
Note also that the weight thresholds in those statutes are about gross weight, and a loaded 26 foot box truck can be a genuinely heavy vehicle. A truck that is under the 26,000 pound rating for licensing purposes can still be over the 10,000 pound line that some state speed statutes use.
Do you need a special license?
For the common consumer sizes in the United States, no. The rental fleets are deliberately rated at or below 26,000 pounds gross vehicle weight rating, which is the federal threshold above which a commercial driver's license is required. Penske states that its personal moving trucks do not require a special license, and Enterprise describes its rental fleet as vehicles that do not need a commercial license. A normal driver's license covers the 10, 15, 20 and 26 foot trucks. Provincial rules differ, and Quebec is a documented exception that requires a Class 3 license for a 26 foot truck.
The practical case for going slower
Legality is the floor, not the target. Three things change once you are in a loaded truck, and all three point the same direction.
Stopping distance. Brakes work by turning kinetic energy into heat, and kinetic energy is proportional to mass and to the square of speed. Both terms move against you in a moving truck. Load the vehicle to three times the mass of your car and the same brakes and the same four contact patches have three times as much energy to shed. Increase speed by 10 percent and you have added about 21 percent more energy on top of that. Then add reaction time, which does not shrink, and the fact that a heavier vehicle takes longer to transfer weight onto the front tires before the brakes reach full effectiveness. Federal figures for the extreme case, a fully loaded 80,000 pound tractor-trailer, put stopping distance at roughly 525 feet from 65 mph against about 316 feet for a passenger car. A rental box truck sits somewhere between those, closer to the car when empty and meaningfully worse when full. You can see how the square law behaves at different speeds with our stopping distance calculator.
Crosswind. A box truck is a large flat side with a high center of pressure. Aerodynamic force rises with the square of airspeed too, so the push you feel from a gust or from passing a tractor-trailer grows sharply with your own speed. At 55 mph a crosswind is a correction. At 70 mph in the same wind it is a lane departure.
Load shift. Cargo that is not tied down turns into a moving mass under braking or cornering, and it arrives after you have already committed to the maneuver. The heavier the load and the harder the input, the worse the effect. Tie down against the walls, keep heavy items low and forward, and brake early enough that nothing in the box has a reason to move.
Knowing your actual speed
Rental trucks are not new cars. The speedometer may be worn, the tires may not be the original size, and the dash may be a long way from your normal reading position. If you want the honest figure rather than whatever the needle claims, run the car speed test once at the start of the trip and compare the dash to true GPS speed, or just keep a live GPS speedometer visible in a phone mount. GPS measures ground speed independently of the truck's tires and gauges, which is exactly the reading you want in an unfamiliar vehicle.
It is also worth logging the trip. Most rental agreements price mileage separately, and the odometer reading at pickup and drop-off is what you are billed on. Our online odometer tracks distance from GPS, which gives you an independent record of how far you actually drove if the final invoice looks wrong.
The takeaway
Towing a U-Haul trailer, treat 55 mph as your ceiling, because that is U-Haul's published maximum and in some states it is the statutory limit as well. Driving a moving truck without a trailer, there is no published company maximum, so the posted sign governs unless the state you are in sets a lower figure for heavy vehicles or combinations. Many trucks are speed limited, but no fleet publishes the setting, so treat any specific governed speed you read as an anecdote. And whatever the legal number turns out to be, a fully loaded truck asks for a slower one. The brakes, the wind and the load all get worse faster than your speedometer suggests.