View Full Version : Single axle vs. dual axle

08-25-2004, 03:29 PM
Anyone know why some boat trailers come with a single axle rather than a dual axle? My dealer didn't have the answer but said that many of the trailers on the east coast are single axle? Why wouldn't Mastercraft (or any other trailer manufacturer) use all dual axle trailers since they seem to handle better. Just wondering...

08-25-2004, 03:35 PM

You can get either a single or a double axle trailer from Mastercraft, your choice. Double axle trailers just cost more. If you are only trailering infrequently, in my case once in the spring to launch my boat and once in the fall to take it out of the water a double axle trailer would provide little benefit.

If you go through the Showroom on this site you will see both types.

08-25-2004, 03:40 PM
Double axle trailers offer more stability when driving at highway speeds. If you have a 20' boat it wouldn't help as much as larger 21-26' boats. Not only does it place weight across two axles rather than one, it offers better tracking on the highway. A single axle however is easier to back and personally I have no problem towing one with my Z71 and do to the tune of 3,000 per year.

08-25-2004, 03:41 PM
Does it have anything to do with the weight of the boat? I was thinking tandem trailers were mostly used for the bigger boats like the X-series and Maristars and such, unless you just wanted to buy a tandem for a PS190.

08-25-2004, 03:42 PM
Sorry Ohio, I must have been typing while you were submitting...

08-25-2004, 04:13 PM
IMO, the Tandems make a nicer looking rig - not sure if 2K better though.....

Single is certainly easier to back.

There is some comfort in knowing that if I blow a tire at 75 MPH on I75, I've got 3 more to help me get out of traffic (never happened thank goodness). Anybody had experience with this?

08-25-2004, 04:24 PM
Had a buddy who had a blowout with his tandem axle trailer on the freeway. He didn't have a spare at the time so he casually pulled over, removed the flat & tied the one axle up so it didn't drag on the ground. Then he drove home & took care of the tire later in the week.
I have a tandem for a 205 & it is a pain to push around in the driveway by hand. Otherwise it pulls great.

08-25-2004, 04:36 PM
I agree generally with size of boat. If you notice the 25-35 ft boats are generally on 3 axle trailer I think tandems ride the boat a little smoother. You do hear the tires squeal/grind if you turn sharp. I don't understand what the difference in backing up is whether it is tandem or single? Comments :confused:

08-25-2004, 04:42 PM
A single axle will pivot easier than a tandem axle. When turning a tandem trailer I think you have side to side slippage of the tires (why you hear the squealing around corners), whereas a single axle trailer will not have this, at least not as much. This is not based on any real knowledge, just thinking out loud.
I occassionally have to move my boat and trailer around by hand. I doubt I would be able to do it with tandem trailer.

08-25-2004, 04:50 PM
Leroy, I guess you're right, it really is more applicable to the turning radius, as opposed to a reverse/forward issue. It just seems to become more apparent in reverse. Tandem limits the radius for the same reason you mentioned - longer pivot point causing resistance and squealing tires due to sliding rather than rolling. When turning, intensified with the degree of the turn, the inside wheels must "slide" sideways instead of rolling. Compare to a sled in the snow. If you pull the sled sideways, one skid must slide around the inside radius of the turn. Same principal.

Hopefully that wasn't more remedial than you were looking for.

bcampbe7, sorry for the dup - we must have been typing at the same time.

08-25-2004, 05:00 PM
Chris and BCambe7 are right on:
Think of it this way, a 20' trailer with one axle will turn left as you pull the right wheel around the position of the left wheel. The right wheel on a dual axle with the same length will have to travel the twice the distance and the left hand pivot point is twice as large. When making a tight turn the tow vehicle will make it through the turn much fast the rear axle and the truck will actually drag the trailer to a square position (squeal).

I blew a tire right before Florence, KY this season and a dual axle would have been nice...but I don't know if the extra cost and maneuverability trade off is worth it.

08-25-2004, 05:18 PM
A properly built single axle trailer will tow beautifully. Athough MC has come a long way with thier single axle trailer I still don't think anyone makes a better trailer than Dorsey.

I have owned them both and I like the single axle much better. The main reason is manuverabiltiy. I can whip it around in my garage by hand and I do not have to pucker when I make a u-turn at the ramp (due to the tandem axle's fighting each other in the turn).

A single axle will not work for all applicaitons since most MFGs use a 5200# axle with 15" tires and wheels. Some boat/trailer combinations are over 5200# and require a tandem. The standard axle used in a tandem set up is 3500# boosting capacity to 7000# total. Most tandems can get by with a 14" wheel/tire since the load is split between the four.

I will say my single axle is much harder on tires. I do tow about 5k a season and I run fairly fast down the highway. In the 10 years I have had this boat I have replaced the tires 3 times. I finally gave up on the goodyears due to seperation; evidently a farirly common mfg defect with the marathon according to my dealer. Twice they came apart on me on the highway at 75+ mph and I have had no trouble shutting it down. There was plenty of carcass left on the tire once it came apart to safefly come to a stop.

When you compare the benefits/drawbacks I like the single axle. My next boat will be on a single axle and it will be another Dorsey.

08-25-2004, 05:35 PM
So what brand of tire do you find holding up better than the Goodyears?

lakes Rick
08-25-2004, 05:40 PM
The only advantage a single axle trailer has, besides cost, is its ability to be moved around OFF of the tow vehicle.. EVERY other advantage goes to a tandem axle....

I am not saying a single axle will not trailer well, it will.. It us usually more than capable of all trailering abilities until weight becomes an issue....

I have had both and my tandem is the only way to go..

My Garage is a daylight basement with the garage door on the side of the house. I have to back DOWN a slope and jacknife my trailer to get it in my garage.. If I can do it with a 23" Maristar on a tandem trailer, yeah there is some squealing of tires, anyone can....

east tx skier
08-25-2004, 05:55 PM
I'd agree with Rick, but I'd also consider the extra cost of tires. If you're trailering a lot or planning to tow over great distances, tandem is just good insurance.

/hoping I never have a blowout.

08-25-2004, 09:39 PM
No doubt about it, if you are trailering on a regular basis..tandem...tandem..tandem. I blew a tire on my
03 tandem 209 and the trailer never moved. Instead
of using a jack I backed the trailer up to the roadside
ditch and let the rear axle "hang" and was back on the
road in 10 minutes. I also has a act on "vandalism" on my
03 197 tandem trailer and did the same thing. Backing a tandem
trailer is easy for beginners, because on the extra drag from the
rear axle. No problems backing in the garage but you do drag the
tires. I have a buddy with a 197 single axle and it sways alot more
than my tandem 197. Also keep in mind with the extra axle gives you
an extra set of disk breaks. This is nice in the case of dumb drivers.
Also, another hint to pushing a tandem into the garage is to lower the jack all the way down this will take alot of pressure of of the rear axle and make it easier to "push" around. My .02cents.

08-26-2004, 07:43 AM
I own a single on my PS 190. No problems at all with it. However - if I had a choice - I would buy a tandem.

As far as the turning radius being different on a tandem - I don't agree unless you're ONLY talking about off the vehicle.

Because of having a place in the flood plain - I frequently move tandem & tripple axle 14x75 mobile homes (usually around 8) into & out of very tight places (2x a year)(we're talking places that the "pros" can't think about getting into). I can put a tri-axle anywhere I can put a tandem. Yes - there is more "slipping" - but that's what the tires are designed to do.

Good point on lowering the tongue when off the tow vehicle to raise the rear tires.

08-26-2004, 08:23 AM
I recently sold my my old boat that had tandem and now have single. For what I do, the single is fine. My boat stays on the lift most of the time. The single does not track as well and sways more.
Ever notice that those bass tournament boats usually have tandem? Those people log many miles.
If I were buying and had an option, tandem all the way.

08-26-2004, 08:27 AM
I'm envious Rick if you can get your 23 Maristar in your garage! I tried once day before and never could!

08-26-2004, 09:49 AM
ChrisG, I think it's pretty well summarized. If your total rig (boat + trailer) is under 3000 pounds AND you don't do long distances, a single axle trailer will work just fine. It has half the number of tires to rot, wheel bearings to replace, and brake shoes to maintain.

If your rig is heavier and/or you trailer your boat a lot, get a tandem. They give you the insurance of a redundant tire (if one blows), and are far more stable at highway speeds.

good luck

08-26-2004, 11:22 AM
Thank you everyone for your responses. I have an 03 X9 with a tandem trailer that works great. I was just wondering what the differences were between the two. It seems that a single axle trailer would not be as stable at higher speeds (over 50mph). By the way, this is a great forum. A lot of knowledgeable people. I'm happy to part of the MC family.

08-26-2004, 08:12 PM
Chris, I've always had duallys, and had a blowout at 70+ in the Sierras one day. As someone else said, all I did was slow down and pull over, put the spare on, and I was on my way. My first choice would be two axles, in spite of the extra costs.

08-26-2004, 08:22 PM
I like the dually trailer as well, but I have to do a lot of moving around by hand with the rear entry garage. Thatís the only reason Iím not willing to give up the ease of use..

east tx skier
08-27-2004, 10:53 AM
Just to raise another question, how fast does everyone tow. As a general rule, for me, I don't go over 70 (usually not past 65). It's not that the rig can't go faster, I just don't like the idea of it. What are your thoughts?

08-27-2004, 11:48 AM
100 km/hr max (62mph) for me. I typically pull with my mooring covers on and I don't want to overstress the fabric. Plus, fuel consumption goes through the roof if I go any faster.

08-27-2004, 12:08 PM
Just to raise another question, how fast does everyone tow. As a general rule, for me, I don't go over 70 (usually not past 65). It's not that the rig can't go faster, I just don't like the idea of it. What are your thoughts?

Yeah stay at whatever speed you are comfortable at. I see alot of people towing way faster than they need to be.

I tow alot and most the time I run 80mph but I do have 3/4 ton truck that is very stable. I am also very anal about my tires, brakes, and bearing; checked and/or replaced every year.

If I ran 65 here in OK I would be blown of the road. Our normal T-pike speed limit is 75.

08-27-2004, 12:16 PM
So what brand of tire do you find holding up better than the Goodyears?

Well this season I put a set of chinesse specials on :D .

I am the kind of person that buys the best to prevent from having trouble so it was very hard for me to buy a set of china tires. There are not many options for trailer specific tires so my choices were limited. My wholesaler had been selling these tires for many years and said he only had a couple of sets ever come back and it was due to overloading. He also sells the Marathon and they were always coming back separated and was concidering dropping the line.

I have logged about 3800 miles on these and so far so good. The jury is still out on longevity though. I'll let you know in a couple of years.......

east tx skier
08-27-2004, 12:27 PM
Diesel, I had always heard of the Carliels (sp) separating, but never much about problems with the Marathons. Still going strong on mine. Sorry you had problems with them. One thing to consider is that they only offer C-rated tires in the Marathons for the 14" rims. To get D-rated tires, you have to go to 15s.

08-27-2004, 12:42 PM
70-75mph. Been faster at night. :rolleyes:

The boat stays true and straight, no swaying. Even with semi's passing me at over 80mph. Won't tell the fastest speed, but it was fast with no problems. Not that I would recommend such speeds. :eek:

east tx skier
08-27-2004, 12:45 PM
Neil, is that a snap on cover? Those covers (at least the old ones)will blister the gelcoat during towing.

08-27-2004, 01:03 PM
Depends on the cover....I tow w/o cover unless conditions get bad. Then the cover snaps on and fits like a glove. This pic is without pole or tied in the back. With the snap up on the gunnel, it does not flap like covers that go to the rubrail. My 02 cents.

east tx skier
08-27-2004, 04:15 PM
Now nobody said "snap-on" cover. Different story.

08-27-2004, 04:36 PM
Diesel, I had always heard of the Carliels (sp) separating, but never much about problems with the Marathons. Still going strong on mine. Sorry you had problems with them. One thing to consider is that they only offer C-rated tires in the Marathons for the 14" rims. To get D-rated tires, you have to go to 15s.

I have 15" six lugs and they are D rated. Tire guy said the same thing about Carlile tires as well.

I am starting to think it's just me............. ;)

east tx skier
08-27-2004, 04:56 PM
Hope you have better luck with your new tires (looks like you are). Hope I have better luck with the Marathons than you did.

08-27-2004, 06:41 PM
Doug, yup.. have a look in the gallery. My mooring covers double as my travel covers -- keeps the bugs off the windshield and allows me to pack stuff (jerry cans, wakeboards) inside the boat without fear of anything blowing out. On long hauls, I take the bimini down and lay it inside the boat as well (keeps bugs off it, too). [Now, if MC only made a tower that folded up nicely]...
I've had this setup on every boat I've ever owned (and my dad before me), never had any damage.

east tx skier
08-28-2004, 12:47 PM
Good deal. I always lay the bimini in the boat sideways around the motor box for trailering. I gave my gelcoat on the gunale (sp) a little rash one time (buffed out easily enough) by trailering with a cover, so I'm pretty leary about it. But I just have the regular old MC cover from the 90s.