
The safe and legal speed for towing a car is almost always lower than the posted speed limit for regular traffic. In the U.S., most states mandate a maximum towing speed of 55 mph, regardless of the highway's limit. This isn't just a suggestion; it's a critical safety measure. Towing significantly changes your vehicle's dynamics, increasing stopping distances and making it more susceptible to crosswinds and trailer sway.
The primary factor is your vehicle's towing capacity, which is the maximum weight it's designed to pull. However, even if you're well under this limit, speed remains a major risk factor. Key considerations include:
Exceeding safe speeds can lead to dangerous trailer sway, a fishtailing motion that is difficult to control and can cause a rollover. The best practice is to reduce your speed, increase your following distance, and prioritize a smooth, controlled drive over haste.
| Factor | Impact on Safe Towing Speed | Key Consideration |
|---|---|---|
| State Law | Typically 55-65 mph | Always check local regulations; 55 mph is the most common limit. |
| Combined Weight | Heavier loads require lower speeds for safe braking. | Gross Combined Weight Rating (GCWR) should not be exceeded. |
| Trailer Type | Flatbed trailers are generally more stable than tow dollies at speed. | A tow dolly lifts the front wheels of the towed car, altering balance. |
| Weather | High winds or rain necessitate a significant speed reduction. | Hydroplaning risk increases with a trailer. |
| Vehicle Type | Large SUVs/trucks handle towing better than smaller vehicles at speed. | A vehicle's wheelbase and suspension are key to stability. |

Honestly, I keep it at 60 mph max, even on a 70 mph interstate. It just feels so much safer. The few times I’ve crept up to 65, I could feel the trailer starting to get a little "squirrelly" behind me, especially when a big truck passed. It’s not worth the stress. I’d rather add an extra hour to my trip and get there in one piece. The gas mileage is terrible enough at 55; going faster just burns money for no real time savings.

Focus on control, not speed. Your braking distance can double when towing. A sudden lane change or panic stop at high speed is incredibly dangerous. I always set my cruise control to 55 mph if the weather is clear. This prevents me from unconsciously speeding up. The goal is a smooth, steady pace. Constantly checking your mirrors for trailer sway is more important than watching the speedometer. If the trailer starts swaying, you must slow down gradually—never hit the brakes.

Think about what you're towing. You've got all that extra weight and a long rig behind you. It's like driving a bus. You need more space for everything—slowing down, changing lanes, turning. Pushing past 60 is asking for trouble. I learned this the hard way when a gust of wind on a bridge nearly pushed me into another lane. Now I just relax, stay in the right lane, and let everyone else rush by. It’s a much calmer drive.

Before you even hit the road, your setup dictates your safe speed. Improperly balanced load on the trailer is a huge risk. You need the right amount of tongue weight—usually 10-15% of the total trailer weight—pressing down on the hitch. If it's too light, the trailer will sway dangerously at any speed. Also, check your tire pressures on both the truck and trailer. A soft tire can fail under the stress of towing at highway speeds. Good preparation lets you drive with confidence at a steady 55-60 mph.


