Dual axle vs single for stability?

[kevinkatz]

i have a 65 caravel with a new axle (single) that i just towed a few hundred miles. it was fine and went well.
the next weekend i towed my little hotrod on a rented u haul, double axle trailer. it seemed more stable. was it the aerodynamics or the low center of gravity of the heavy car hauler trailer?
so the question is------are double axle airstreams more stable than single axle trailers?

[SteveH]

Originally Posted by kevinkatz

i have a 65 caravel with a new axle (single) that i just towed a few hundred miles. it was fine and went well.
the next weekend i towed my little hotrod on a rented u haul, double axle trailer. it seemed more stable. was it the aerodynamics or the low center of gravity of the heavy car hauler trailer?
so the question is------are double axle airstreams more stable than single axle trailers?

It could have been both, but to answer your question, a tandem axle trailer is more stable, but a single axle is easier to pull. The single has less rolling resistance.

[overlander64]

Greetings kevinkatz!

Owning both a single axle (Minuet) and a tandem axle (Overlander) Airstream product, I can report that my experience is that the stability of the Minuet is highly dependent upon carefully balancing the load with a strong bias toward the front of the coach ahead of the axle. In fact, it has a front mounted water tank and if it is not full the coach does not behave as well as when the tank is full. Condition of the axle can also have an impact . . . my Minuet handled much better once the new axle and shocks were installed. Using Reese Strait-Line hitches with both coaches makes them handle like twins .. the Overlander is much easier to back, however.

Kevin

[85MH325]

A point of semantics... a trailer with two axles are "tandem axles". An axle with two wheels on each end is a "dually" or "set of duals". Tractor-trailers, for example, have tandem axles with duals.

Now, that said...

Over the years, I've towed a 16' Bambi single, a 23' Safari single, a 26' Overlander tandem, and a 34' tri-axle as well as a host of other trailers. I have a Bigfoot 25' tandem axle trailer now.

The biggest difference is ride quality. By far, the smoothest riding trailer was the tri-axle. I could leave anything inside anywhere and it didn't move at all, even over the seemingly roughest roads. One time I was quite amazed to find a forgotten coffee cup on the dinette table in exactly the same place it was left after a five-hour drive.

"Stability" is subjective and has to to with many factors including center of gravity, ball to axle distance, and weight distribution (both of the trailer and load). Perhaps of even more concern for "stability" is the competence of the tow vehicle. A trailer that is a nightmare to tow behind one vehicle can be amazingly well-behaved behind another. Tires, suspension, wheelbase, tow vehicle weight, and hitch setup all have their role to play there, with hitch setup being perhaps the most important.

I tow (and have towed for many, many years) with a Reese Dual Cam I have the Straight-Line setup on my Bigfoot. I bought an '07 Titan last year as my new tow vehicle, and just threw the hitch together to tow the trailer fifty miles earlier this spring. It was white-knuckle all the way there and back... and this in a trailer that was extremely well-behaved behind my Excursion and Born Free motorhome.

An hour of hitch-readjusting later, and the next several hundred mile trip was like just pulling a cloud. Same truck-trailer combo... just set the hitch up properly.

So... I guess that's a long-winded way to say that the number of axles has less to do with trailer stability than a host of other factors.

Roger

[SteveH]

Originally Posted by SteveH

It could have been both, but to answer your question, a tandem axle trailer is more stable, but a single axle is easier to pull. The single has less rolling resistance.

My basis for the above statement is past experience. In about '75 or '76 we owned a 20' Argosy(forgot the year, but I think '73), single axle trailer, and towed it with a '74 Chevrolet 3/4 ton pickup. We used a Reese Dual Cam hitch...the original version with the "U" bolted plates. It towed fine. Later, we traded for a 24' Argosy, tandem axle, kept the same hitch, and towed with the same truck. The difference was noticeable. The 20', although it was easy to tow, did not have the stability of the 24' tandem axle trailer. And, the 24' tandem took a noticable amount more power from the truck to tow it down the road.

I'm not saying that either one towed badly, but the differences were obviously there.

[garry]

I have had and pulled both types.

Single = less expensive to operate, better gas mileage, less stability.

Tandem = more expensive to operate but better stability.

Example a small boat trailer with single axle one person can move it around to hook up but the same boat on a small tandem axle you have to back up to the trailer as it can't be just pushed around.

Garry

[Grumpycamper]

Short trailers without much tongue weight tend to rock and roll a bit. The reduced weight in the front of the Caravel without the battery, propane tanks, water tank plus not having the regular extra stuff for camping may have an effect on it. I'm sure it pulls fine, but would probably feel better with more tongue weight. The Caravel looks great. We are saving the Airlight for you. Jeff

[snake]

I have two very similar Airstreams, a 19' Bambi single axle, and 21' Sovereign tandem axle. The two trailers are within 10% of each other in term of length, weight, and tongue weight.

Having towed both trailers with the same tow vehicle and weight distribtion hitch the tandem is superior in terms of stability, both on the highway and on winding mountain roads. It just feels better. Brakes feel smoother too.

The tandem is smoother riding, particularly on rough or dirt roads, judging by how the stuff inside looks after towing.

An advantage to the tandem is that if you have a flat you can pull the good tire up on a block of wood to change the other tire, and even in an emergency remove the flat tire and wheel and proceed slowly to where you can get service.

[wolfpack]

having had several trailers over the years, I was initially looking for a single axle AS but when I found a great deal on a dual axle overlander that was too good to pass on I purchased it.......I have read alot on this site about axles and now that I have a dual axle trailer, I wouldn't have it any other way. the tandem tows much, much better, I was impressed with how stable it towed and when I drove 600 miles to go get it, I had no sway bar, no equalizing hitch, just simply hitch on ball and towing on winding mountain roads, freeway, windy, etc I am totally sold on the tandem axle, much safer too if you ever have a blow out.

[barts]

A double axle trailer has much more "damping" in terms of its motion. You can move a double axle trailer by hand fine in a straight line, but turning it, even a small amount, is much more difficult. As a result, you'll definitely feel more drag in low speed tight corners w/ the double axle - but the trailer also tends to track much better at speed.