Tandem vs. Single Axle

[Adeline]

When I purchased Adeline in '89 I don't think a dual-axle was even an option.

All of my boats have sat on single-axle trailers although I've towed others' dual-axles.

Snowmobiles on singles and duals. I've owned both.

Utility trailers all single.

Thousands and thousands of miles.

Duals trail smoother.

Redundancy is good.

It's also twice as many parts that could fail.

A flat tire or spun bearing or stuck wheel-cylinder is going to sideline any trailer.

Single or dual you're on the side of the road.

One last thing, if you need to "muscle" a trailer around the driveway it better be a single axle because you're not going re-park a dual without hooking it up.

[texasair]

If the tires, hubs and axle are rated for the load, a single axle trailer works fine.

With a single axle there is no alignment wear or scrubbing from turns. Also, trailer hitch height to keep the load even on both axles is not an issue with a single axle.

Our single axle trailer has a heavier 6-7000 lb rated axle and hubs. I believe most tandem axle trailers in this range come with a pair of 3,000 or 3,500 lb axles.

We have had no issues in over 8,000 miles towing our 22 cruiser.

We usually travel with full fuel and water.

I do use Load range E, 10 ply rated tires, and in the above 8,000 miles we have had 1 high speed blowout. It was a non event. The trailer tracked straight with no control issues, we made it to a safe area and put on the spare. There was no damage to the boat or the trailer. I do carry 2 spares and a spare hub with bearings just in case. I also inspect and repack the wheel bearings each season.

A tandem axle trailer is nice, but a well maintained single axle trailer will do the job.

Our tow vehicle is a Chevy 1/2 ton pickup.

[colbysmith]

I'll try to upload a picture later, but during my last trip, I was glad I had a tandem axle trailer. Had a blow out on the front drivers side trailer tire. Was able to get it another 2 miles down the road to get off the interstate. And the spare came in handy too. Probably would have been a lot more exciting with a single. It did take me an hour to get the spare on though as I had several stop to admire and ask about the boat.

[thataway]

The question I have is how old are the tires--and do you know what caused the blowout? If it was a road hazard (bolt, pot holes etc) that is explainable. We are at the point in life were we change out RV and trailer tires at 5 years by date of manufacture stamped on every tire. Expensive. Charlie had 2 blow outs on the trailer tires of the Tom Cat 255 when towing to VA a couple of years ago--the tires were 5 years old (at least of use)--and only a few hundred miles on them.

Glad that there were no issues with the trailer and you safely made the 2 miles.

We also check the temp of the tires of all vehicles about every 2 hours (exception are the car and SUV--both of which have tire pressure moniters built in).

[Sunbeam]

[T.R. Bauer]

I have had a couple blow out tire failures on single axle trailers at freeway speeds and other than the, "oh crap I have a flat tire vibration," that went through the trailer and truck, there were not any handling issues at all. The laws of physics states the trailer is going to go in the direction it is going unless a great force causes it to go in a different direction. A flat tire just doesn't change the direction of the force much. The bottom line is the trailer follows the truck - good tires or not.

Bob's advice is good - tires over 5 years old are generally bad news. In fact, I bet 95% of tire problems comes from tires over that 5 year mark regardless of treadlife left in them. Avoiding a blow out certainly makes what trailer type you have a moot point.......

[DuckDogTitus]

I've never had anything but tandem axle for any boat over 500lbs and having had a blowout on the highway with the tandem I assumed that I was better off for having it and being able to limp off safely. When we were shopping for a C-Dory we wanted a tandem. even the single trailers we looked at I considered always what my cost would be to upgrade trailers in the near future.

never had towed a larger boat with a single axle, it may be silly but I like my tandem axle and feel its worth a few extra bucks. also, it looks cool.

[PaulNBriannaLynn]

We had a Glasply previous to our C-dory, and was heavier to tow. When we first purchased it, it came on an single axle trailer.

On our first attempt to take it out, the right side tire seperated at 60 mph, taking most of the metal trailer fender with it.

It was really scary keeping the trailer on the road, but I was able to stay out of the ditch and get safely off the road. The tires were most likely over 5 years old and that was likely the cause. I beleive the trailer would have pulled me into the ditch at nearly 60 mpg, if i hadnt been towing with a heavy duty tow vehicle.

That trailer bounced around alot on the highway, and also seemed more sensitive to steering changes when backing up. In high side winds, it also seemed to get blown around more.

When it finally deteriorated from saltwater, we upgraded to a double axle and the handling was a night and day difference. I can't stress enough how much better the double axle towed down the highway.

[Sunbeam]

[colbysmith]

Here is a picture of that tire, after I had removed it, while waiting to get the new one next to it mounted.



The boat and trailer are a 2007, and since the previous owner didn't trailer much, most the mileage on the tires are mine. I've probably put several thousand miles on them. All looked good when I checked everything about 50 miles earlier. I run 50 psi of Nitrogen in them. (I changed over to the Nitrogen maybe 1000 miles or more earlier.) I don't know if any foreign object was picked up on the road or not. This was the forward tire, but I think run pretty much in line with my Highlander footprint. These are Goodyear Marathons. I assume they are a good tire, load range C. The boat was not overloaded, and I was only running 63-65 when this happened. When it happened, other than the loud blast, I did feel it "yank" a bit. With the Tandem, I at least could pull it a ways to get off the road. Without that other tire on that side, I would probably have been riding on the rim only. I have pulled some smaller single axle trailers in life, but just as you guys argue for twins or kickers, I see having a tandem as a more safe operation.

[Sunbeam]

[colbysmith]

I should add, these tires were in good shape. IE, no sun cracking. I keep them covered, and I believe the previous owner pretty much kept the trailer covered. I've had trailer tires last much longer than 5 years, when properly cared for. And while I have sprayed some of that tire magic on them, I don't make it a routine. (That stuff is worse for the tire, than just letting it set!)

[Sunbeam]

[PaulNBriannaLynn]

Sunbeam[/quote]
How did the weight rating of the trailer compare to the weight of the boat? Just wondering if that might have been a factor. On our weight boats (22's), it's perfectly possible to have a single-axle trailer that is generously rated, but I would think that as a boat gets larger/heavier that at some point it might no longer be an option.

Sunbeam, I'm guessing our old boat was right at the cusp of requiring a double axle. That being said, once we replaced those old tires.... we got many thousands of trailering miles on that old Caulkins before it finally bit the dust.

When we did get our double axle, I was no longer "white knuckling" the steering wheel and it just seemed less scary to tow.

The 22' c-dory is light enough that a double axle is not really necessary especially with a large tow vehicle.

[Sunbeam]

Thanks for the follow-up info.

Sunbeam