Car-top vs Trailer

My wife and I are driving from Chicago to Flagstaff in January. I fully intended to put our two 17’7" kayaks on the roof of our Golf. It just occurred to me that perhaps modifying my windsurfing trailer (which is really a Hobie 18 trailer) to tow my kayaks likley has an aerodynamic advantage, but a rolling resistance disadvantage. Has anyone ever done a fuel economy experiment like this? I thought if I set it up so that the bows are close to the trailing roof-line and the sterns are closer to the ground I could minimize the wake. Call me crazy…

Add wheels, Add gas $
Whenever I hook up the trailer, laden or not, it defitely puts a dent in the gas mileage. Not so much on the power (Trailex alum. trailer) but I notice it at much more frequent gas stops.

Have fun on the trip.

See you on the water, or road in this case,


I can’t answer your question directly, but I can say that the air immediately behind the Golf is considerably messier than it was behind my previous tow vehicle (a largish ChryCo 90’s sedan). This as evidenced by how much wiggling the boat does riding on the fairly-flexible Trailex aluminum trailer I have (worse with the GTI). So I wouldn’t count on any aero benefits to trailering, necessarily, as pulling through such turbulence is bound to create considerable drag.

And this doesn’t answer your question either, but I think I’d much prefer renting a couple boats when I got there. Would make the drive itself far more pleasant.


That’s what I thought. I appreciate the comments.

My thoughts were that 10 days of paddling around Lake Mead and Mojave warrants car-topping instead of renting. Reasonable?

if all you could manage to rent were a couple rec boats. But if you can get touring boats I’d much prefer that option, and it would be a chance to try out something different than what you have.

The Golf is kind of a lightweight hauler for that sort of journey. I know people do it, though I wouldn’t want to.


other considerations
I don’t know about the mileage, though I notice a big reduction when I car-top.

Trailers are quite a bit more work. Chances of flats, watching the bearings, driving in traffic/parking/backing. Also, with the boats closer to the road, stone-chips and dirt are a bit more likely. I have a trailer, but only use it for gear if the car is already overloaded.

I am really interested in the mileage question, though. Please post results if you decide to try.

Enjoy your trip.

I think it depends on the kind of trailer and condition and how much you like your yak. I know I would take mine if I could, on a trip like that.

Besides, it would make a great study. If you have confidence in your trailer there are plenty of people here who would like a firsthand account of the MPG difference.

Speed limits a factor?
Are there many states with lower spped limits for vehicles with trailers that you will cross?

Or is the Peoples Republic of Kalifornia the only state that wants folks with trailers to do 55 when the posted limit is 65 or 70?

I know from experience that it can be a real drag trying to be legal at 55 when everyone else is doing 70-80.

First Trailer flat ever
This weekend I had the first trailer flat ever about three miles from home. I forgot the

lug wrench (it was in the sailboat)so we had to go to Walmart and get one so we could change the tire. For what it is worth AAA will not cover a flat on a trailer hauling boats. In the past I just made certain I had a spare because I could always call AAA to change the tire, but they wouldn’t send anyone out.

Still for long trips I’ll still use the trailer because of the easy loading and better gas milage and wind handling.

Rolling resistance is negligible

– Last Updated: Nov-27-06 8:44 PM EST –

Your results probably wouldn't be the same as mine due to large differences in type of tow vehicle, but rolling resistance towing two kayaks is pretty low. It's not like you're towing a car or an Airstream. The kayaks weigh less than 150 lbs and the trailers to tow them are usually fairly light, too. Dedicated kayak trailers weigh about 250 lbs.

Our snowmobile trailer weighs maybe 400 lbs unloaded. I can pull the loaded trailer around on flat ground myself and I'm only a 5'2" female. So much for rolling resistance! (Working against gravity--up or down hill--is another story.)

My husband and I normally tow our kayaks on the trailer and have found virtually no effect on mpg with V8 and V6 trucks. This summer, we took a long road-and-ferry trip for which we rooftopped the kayaks on his Chevy Tahoe. His normal highway mpg dropped about 2 mpg (more than 10%). In our case, the minimal rolling resistance of the trailer is a better choice than adding windcatchers on top of the vehicle.

Best to do a test run before your long trip and determine what really is the case with YOUR set-up.

My experience
Two kayaks on the roof rack drop the mileage between 2-3 mpg. If we keep the top rack of the trailer empty so that it drafts our minivan well we drop the same 2-3 mpg. With boats on the top rack of the trailer we drop about 4-5 mpg.

Bikes on our roof rack drop our milage more than the kayaks, about 4mpg.

I’d just put them on the roof rack and go if I were you. You really have to pad the trailer and load the boats securely so that they don’t get beat up on a long trip.

I’d go for renting. I was just up at Lake Mead this morning and we canceled going kayaking because of the high winds and a storm coming in. I don’t think I’d want to be out for ten days in January, but then I’m not into wind and rain!

Lake Powell Info

I did a kayak trip on Powel with friends last year and rented the boats from Twin Finn in Page. Good service.

One thing to be aware of is unless you have a LOT of time, you’ll spend most of your trip just paddling up the lake to get back. Believe it or not, vehicle shuttles are illegal unless done by a concessionaire and they don’t do them.

Most folks do what we did and rent a houseboat, shoot up the lake, and do day trips of the boat. It was really pretty fun because you have a full cooking galley and beds at night rahter than needing to break camp every day. If you bring your own food, which you’ll need to anayway, it’s not too bad in cost, although I did have 10 people to split the houseboat rental.

Good luck


trailer towing
Interesting topic !

I would worry less about aerodynamics and more about the transport vehicle springs. Many boat trailer suspensions are sprung for heavier weights than that of two light kayaks. A long trip on a heavy sprung trailer could loosen up fittings or break components easily.

Your car, truck or SUV is sprung more softly and would probably be less jarring to a kayak. There’s always risk when transporting long distance and I’d consider the rental options too.

Car-Top vs Trailer
My family and I have driven across most of America and much of Canada with canoes and kayaks both “in tow” or “on top”…sometimes both. And mileage is very important to us, but so are some other considerations. Here’s what we’ve discovered:

• On our vehicle “a full size van”, the mileage drop is almost the same for the loaded trailer as it is for the car-toping trip, but the trailer carries more than the car-top.

• Ours is a modified trailer with an expanded metal floor to store supplies on, dry gear on, and to protect the canoes and kayaks from the road debris.

• The trailer will hold up to 7 kayaks and/or canoes, but is light enough to move by hand. However, it is heavier than the super light weight commercial built trailers. It does track extremely well behind the van…never a problem.

• Probably the biggest advantage of the trailer is to place cargo on the trailer that would normally take up room in the car, which makes long travel days on the road Much Much more pleasant, and helps stabilize the trailer in heavy winds.

• We use the car-top for shorter trips. But I need to warn you, especially if your driving a “fuel efficient” vehicle, the little extra resistance on a vehicle loaded for a road trip, may be all it takes to force overheating or other horse power related problems when crossing high altitude areas or steep mountain ranges like the Rockies. Having crossed them many time is both Canada and America, with and without canoes or kayaks, and with trailers and with car-top, I can speak first hand to this.

• On the downside of trailers, simple but essential maintenance is a must, but is cheap insurance. Also, you need to check both your route and overnight itinerary. Some tourist traps don’t allow trailers at all, some don’t allow long trailers, and most welcome either. Hotels often have parking restrictions, but will usually have a solution ready. Some campgrounds only allow for a single car at a sight, but most of these have alternate accommodations for remote trailer parking.

• On a closing note: Just because you have a trailer, doesn’t mean you have to use it, but if you don’t have one, you can never take advantage of what it has to offer….oh, and be sure it has a long tongue or you might have trouble on very tight turns. After years of traveling incident free with a moderate tongue length, my brother in law backed our van up one day and put a canoe bow through the back window. We added a couple of feet to the tongue after that.

Happy trails,


Trailer vs. Topper
I paddle every weekend and our club takes many multi day excursions. I started with an Excursion with Yakima racks on top. I got tired of the four ft. step ladder. I didn’t notice much change in mileage carrying boats/not carrying boats but it could have been because of the diesel. I sold it and bought an Outback. Carrying three boats at speed caused a four-six mpg drop. With the racks on and no boats, a two mpg drop. It was easier to load boats but I couldn’t put my tandem on alone. I sold it and got an Armada. Terrible truck for kayaking as you have to use the factory cross bars. Again, I was also tired of loading boats up high and climbing all over the truck to secure them. I just purchased a RackandRoll Trailer. Awesome suspension and made to use Thule and Yakima rack systems. I can load the tandem by myself. It’s now a piece of cake taking my boats. Of course some places you go with a trailer may be difficult accomodating a trailer and in some places it may be harder to maneuver. Oh well, life is a compromise.

Good luck and I’m sure you’ll make the right decision.