Towing a trailer at highway speed?
June 10, 2007 5:56 PM   SubscribeUHaul cites 45 MPH as the "recommended maximum speed" for towing their trailers. What's the reason for this recommendation, and is there any safe way to go faster?

Let's say I wanted to tow a trailer safely at 55 or 60 MPH on the interstate.

Would I need better equipment than UHaul offers? Modifications to my car's engine or brakes? ('95 4WD Legacy wagon, if it matters.) Specialized driving skills? All told, how much practice or preparation could I expect it to take?

Or is that sort of speed really unreasonable for anyone with any gear?
posted by nebulawindphone to Travel & Transportation (26 answers total)
FWIW, I pulled a uhaul trailer for a distance of around 250 miles averaging around 60 miles per hour.

I suspect that the maximum speed is exceeded more often than not.
posted by davey_darling at 5:59 PM on June 10, 2007

(Ah, yeah. Pretend there was another option in my post — "Or are they just covering their asses?")
posted by nebulawindphone at 6:05 PM on June 10, 2007

It usually has to do with the size of the tires on the trailer being smaller than your average car's tires. If you car wheels are going along the road at 45 mph, say, then if the trailer's wheels are smaller than you car's, they will be spinning faster, and thus create more heat due to friction with the road and the tire's deformation on the contact patch, which could lead to a blow-out.

That's not to say that there isn't a safety factor built in to the 45 mph limit, but it probably wouldn't be wise to travel much faster than that, especially in hotter climates.

Here's the math:
rotational speed, w, is related to linear speed, v, by the radius of the tire:

Since the linear velocity is the same for both tires (45 mph), then rotational speed is inversely proportional to radius, or as radius gets smaller, the tire spins faster (and creates more heat).
posted by toomanyplugs at 6:07 PM on June 10, 2007 [1 favorite]

Another reason why it's unsafe: the trailers don't have brakes of their own, so if the trailer builds too much momentum and you try to stop, and the trailer doesn't then you would start to have problems.
posted by martinX's bellbottoms at 6:21 PM on June 10, 2007

I have driven faster (60-70) from the east coast of the U.S. to Seattle, but I can't say whether I was just lucky. I probably took a year off of my life looking in the side view mirror waiting for that U-Haul trailer to go flying off into the ditch. But I made it without incident.
posted by jiiota at 6:21 PM on June 10, 2007

Chalk up another response from someone who has blindly disobeyed the "recommended max" on a u-haul trailer for a long-distance, cross-country move (and am about to do so again without worry in my heart).
posted by maniactown at 6:38 PM on June 10, 2007

I got passed the other day by a genius in a minivan, Aerostar I think, on 101. He was towing a U-Haul in the fast line.

I had the cruise set at 77 and he blew past me. If he was only doing 90 I'd be surprised; looked like closer to 100. The Aerostar was all beat up, dented and scraped, on the passenger side, too, like it'd hit a wall at some point in the not-too-distant past.

This guy was totally out of control, but he didn't die. About 2 hours later he passed me again, again doing 90+; I guess he'd stopped to eat or gas up.
posted by ikkyu2 at 6:38 PM on June 10, 2007

It's a CYA move from their lawyers. I towed a U-Haul from Minneapolis to Phoenix which involves going through parts of the Rockies, and didn't have any trouble going 65 for most of the way. Just be a safe, defensive driver and use your common sense. Stick to the right lane, don't try any fancy passing moves, and slow down to 50 or 55 if things get hairy for any reason.
posted by TungstenChef at 6:40 PM on June 10, 2007

I have pulled Uhaul trailers (including one trip from Colorado to Portland, OR) and exceeded the advised speed every time. Uhaul is covering their asses. It is frustrating. Just be safe and realize that it will take you more time to gain speed when passing and be careful going up and down hills.

With a Subaru and a little trailer you will have no problems at all. These are very easy trailers to work with.
posted by fieldtrip at 6:41 PM on June 10, 2007

Re: martiniX's bellbottoms comment,

I was in an accident driving from Las Vegas to Houston three years ago. I was in an old band's touring van that had been inspected and insured just a week before the trip, and which was also towing a uHaul flatbed with five Vespas on it. Just inside of Hoover Dam there was insane tourist traffic, and the stop-and-go repetitions put enough strain on the van that the brakes started sticking. Several hours later, just outside of San Antonio, we came up over a hill only to see a semi truck slam on it's brakes in front of us. The combination of the downhill momentum, the slow reaction time of the driver (NOT me, BTW) and the weight behind the van caused us to become the delicious vanilla filling in a multi-car Oreo.

This is just anecdotal, by the way, but the entire time (24 hours from Houston to Vegas, then 24 hours back) we were on highways driving at highway speeds. Your experiences may vary, but I wouldn't do it again.
posted by Brittanie at 6:59 PM on June 10, 2007 [1 favorite]

This is a guess, but I suspect there's a practical as well as a legal reason. The average trailer-hiring customer probably just isn't used to driving around with the extra weight and change in balance.

Most can adjust quickly, but unfortunately there are many drivers who are capable of landing the car they drive every day in a ditch; adding a weighed down trailer just makes it more likely.
posted by mogotron at 7:02 PM on June 10, 2007

I helped my girlfriend move out of her apartment in Philadelphia and into a storage unit for the summer back in 2005. We couldn't get the truck until 3:00 pm the day of (though we had reserved it for 8:00 am), and the storage unit in Manayunk closed at 7:00 pm. Four hours to completely empty an apartment and drive through rush hour traffic on the Schuylkill Expressway (I guess we could have taken Kelly Drive, but wtf). We did it, in the rain, and finally emptied the truck into the unit by 9:00 pm. And then found out THAT THE TRUCK'S HEADLIGHTS DIDN'T WORK. U-Haul's response? "Sorry, that's your problem." I kid you not. So we had to leave the truck in Manayunk, take the bus back to Philadelphia, and then borrow a car to pick up and drop off the truck the next day. No refund, no discount. Screw U-Haul.

We've used Budget ever since with not one problem.
posted by The Michael The at 7:21 PM on June 10, 2007

I will just chime in with a note that driving with a trailer is much different and harder than driving without, but the difficulty only shows up in situations that are already difficult, which leads drivers to believe that it's easier than it is. If any difficult situation comes up, and you have a trailer and are going fast, you WILL crash.

Frankly, the odds are that no difficult situation will come up. Even if you zoom across the entire country, you probably won't be cut off or blow a tire or anything like that. So you'll probably be fine going 90 with your Uhaul bumping along behind. But if something happens, that trailer is going to take off and your car is going to be following merrily behind, and they'll find pieces of both strewn across half a mile of highway.

I guess what I'm saying that a trailer decreases your recovery ability and increases the severity of the resulting accident. If you still feel comfortable driving fast with that, go ahead. Driving 45 is one way to cut down on those risks, though.

(I was almost killed in a accident caused by towing a trailer that occurred at about 45-50 mph in a light rain. A car merged onto the freeway in front of us going about 30 mph, the experienced driver slammed on the brakes to avoid rearending the car, the trailer jack-knifed.... The car that caused the accident kept going without stopping. Needless to say, if there had been no trailer, there would have been no accident. In that light rain, 45-50 mph while towing a trailer was TOO FAST for the conditions.)
posted by jellicle at 7:43 PM on June 10, 2007

One word - jackknifing.
posted by randomstriker at 7:52 PM on June 10, 2007

Please don't do business with Uhaul. They are truly an awful company.

Even if you obey their recommendations, their equipment can still kill you.
posted by wfrgms at 8:09 PM on June 10, 2007 [3 favorites]

Having just recently towed a Uhall from Denver to Raleigh I can tell you that getting up to 60mph should generally not be a problem, depending on the road. However beyond 60 with a decent load towed by a Dodge Dakota truck we found that it swayed a little tooo much... led to a few scary moments.

ALSO if you have a trailer with only 2 weels and not 4 be careful, we had one tire blow out on us one year with only two wheels and we nearly died. I imagine that it is a bit safer when you have four wheels as when one of the four blows out it does not lose control as much. Either way CHECK YOUR WHEELS, especially if you are driving at highway speeds

Safe driving!
posted by DetonatedManiac at 8:18 PM on June 10, 2007

Almost 900 miles from TN to TX between 60 and 70. Hauling a ten footer behind an olds 88. No problems (unless you count overheating occasionally) and it was completely (over)loaded to the roof. Your mileage may vary, literally.
posted by IronLizard at 8:39 PM on June 10, 2007

Note that U-haul is very careful about their trailer rentals, for the most part. My Land Rover can haul 5500 lbs if the trailer is braked (the big U-haul auto trailers have surge brakes), but they would not rent me a trailer to haul a 3000 lb car (their trailer weighs about 2000 lbs) because the load would exceed the weight of my car.

I've hauled U-haul trailers up and down I-5 without trouble; but running a trailer is a lot different than running solo, and running a heavy trailer on a marginal vehicle is a real recipe to get in trouble.

Stick to the slow lane, give yourself TONS of braking room, and you should be OK.
posted by maxwelton at 9:25 PM on June 10, 2007

It's just like dosage recommendations on over-the-counter pain meds -- yeah, you can take 4 200mg ibuprophens, and you probably won't die, but they're not responsible for what happens if you do.
posted by M.C. Lo-Carb! at 7:35 AM on June 11, 2007

yeah, you can take 4 200mg ibuprophens, and you probably won't die

Not to de-rail, but that's the equivalent of the 800mg motrin that doctors and dentists prescribe regularly. Great way to avoid paying a premium at the pharmacy counter.
posted by IronLizard at 9:49 AM on June 11, 2007

First: the bigger trailers do have breaks. Also: I was once a passenger in an old minivan with lousy shocks that was towing a large U-haul trailer. Sometimes at a little past 70, the minivan would start rocking back and forth in a pretty scary way. But things were ok when we kept the speed down to 70 or so. Probably 65 would have been a better idea.

Also, U-Haul was pretty unhelpful over the phone when we had trouble finding the drop-off location (miles outside the town it was supposed to be in). So be sure to have a map showing the drop-off location before you start the trip.
posted by washburn at 10:20 AM on June 11, 2007

Consider selection bias: The people who were towing a trailer at 90mph and DID have something happen are probably much less likely to be here to talk about it. Here's somebody on LJ talking about their recent jack-knife with a trailer. Imagine that, with more mass and less air resistance from the trailer.

N'thing that you're more likely to get ripped off by U-Haul than to lose with a scratch-off ticket.(3 time customer, every time's been worse. Never again. Did my last with Ryder, was much happier.) N'thing that they don't maintain their equipment worth a fiddler's damn.
posted by Orb2069 at 4:42 PM on June 11, 2007

Selection bias? Perhaps you're guilty of confirmation bias. No one is suggesting the poster actually drive 90 miles per hour with a trailer, or at all, for one thing. Anecdotes about trailers are worthless for statistical purposes. Even so, if you're going to present us with one, at least make it one that, you know, actually involves a U-Haul trailer.
While I certainly didn't enjoy my trip (my shocks WERE good at the time, no longer) nothing untoward happened as I'd inspected the trailer rather carefully and driven it around the day before leaving. The cause of most accidents involving trailers are a lack of experience with a heavy load pushing on your vehicle and improper loading. You need a good 60/40 (front/back) balance and everything heavy needs to be on the bottom. If the trailer isn't full, the contents must be braced or securely roped in place to avoid weight shifting at an inopportune moment. Around a sharp curve, for example.
I can't say that I enjoy using the things, but they sure are cheap if you don't use any of the 'extras' sitting in there (dolly, blankets). Make sure the zip ties they use to check if they've been moved are all good before leaving the lot (They're easy to break, it's how they charge you far over what you were expecting. As a result, some truck stops have taken to carrying those little ties. ;) )

Take your time, inspect the trailer and get used to hauling it slowly at first. Always brake early, stay AWAY from the traffic in front of you and don't make any sudden moves with the wheel. The trailer hitches (hideaway type) they offered six years ago were fine, I don't know about now. Mods to your car will depend on how much weight you'll be planning to carry around. I doubt it's worth your time and money to soup up your brakes. If that turns out to be necessary you may as well just rent a box truck.

posted by IronLizard at 5:24 PM on June 11, 2007

Selection bias. - The dead rarely pop up and say 'Doooooon't doooooo iiiiiit!' on AMF, so asking a question here decreases your chance of hearing from them.
posted by Orb2069 at 4:23 PM on June 14, 2007

About ten years ago a friend of the family managed to light a u-haul trailer on fire. The wheel bearings were worn out, and the friction made everything hot enough to ignite the rubber tires. I think it would have happened at 45 or 60 (the speed he was going) though. Moral of the story: u-haul sucks.
posted by Nothing at 2:01 PM on June 24, 2007

U-Haul International is the nation's largest provider of rental trailers. A Times investigation finds the company's practices raise the risk of accidents on the road.
posted by meehawl at 2:19 PM on June 24, 2007

 In 1971 J. Standard Baker Quoted " Drivers Towing Trailers  Are Four (4) Times As Unsafe As Those In Cars Alone! 

Fact:  The Government has really ever done a "Wind Tunnel" test like they have with cars.....EVER...EVER...EVER

To show how much "Trailer Sway" is created by all the different vehicles that tow.

Every car and every Pick Up that tows a trailer creates a different pattern of win resistance and air diflection

We demand a comprehensive government study on every vehicle that can "Tow" anything and do a "Wind Tunnel" test at

45 MPH and show the results

55 MPH and show the results

65 MPH and show the results

75 MPH and show the results

We demand a comprehensive test to determine the most dangerous vehicle that can tow a trailer and at the speeds above and then create the safest vehicle to tow a trailer list.

Then a nation "Safe Towing Speed" where all over the county we have a "National Safe Towing Speed"

I already know the lobbiest will be going crazy to stop our questions and suggestions.

Why is U Haul so afraid....because way back in 1971 the "Rental" companies and Trailer Companies said this to NHTSA.

"If people knew how dangerous it is to tow a trailer they would not rent one"

The Newest Victim Of Unsafe Towing U Haul's Ask Us Who She was