triple axle trailer vs. double axle trailer
 

Is there a upside to have a double axle trailer with large tires compared to a triple axle trailer with smaller tires

Maybe the slight decrease is tire replacement costs and you will pay slightly more tolls in some places that charge per axle. Other then that no downside, I vote for triple axles.

triples, if ever your have a flat tire you can always keep rolling on the other. if dual axle, get a flat, and if you don't have a spare tire, you are done. so changing 6 tires on the long run is cheaper and less trouble than being stuck at night on the road with your child aboard,, trust me. I now have a triple, with 2 spare tires!

tandem dually

This topic has been covered before. Triple definately over a tandem. See this thread and my post in it below:

http://www.offshoreonly.com/forums/s...=tandem+triple

It depends on the size and weight of the boat.

You can easily have a 30 foot boat that I would much rather have a dual axel under then a tripple. Myco uses dual for most of thier stuff under 30 feet. I sized up all my stuff on my boat and I can get a blow out and still run no problem on one tire. My boat is 8500 pounds full of fuel plus the trailer. Each axel is rated for almost that and the tires are rated for close to that as well. So I guess we need more info :D

Tandem dually!

I have lost a inner tire and still pulled it 20 miles to rest area to throw the spair on.

I have two 10K HD axles and my tub is north of 13,000lbs

I find it easier to manuver then tripples also.

Ultimatley gooseneck tandem would be the best.

What size boat are you looking for a trailer for??

I have a triple axle trailer that is coming up for sale shortly

30' concept

Yes, tandem dually is the ticket. Triples can be tougher to turn in tight spots, but prefer it over a tandem(single wheels). Triples also seem to track better.

A 30 Concept should be fine on a tandem. CC or closed deck? At most you can do a tandem with 5k lb axles. If you need to go with the bigger axles, you won't save much money up front, but maintenance over the life will be less with the tandem. With the money you save, buy a spare wheel-tire, hub and spindle. And don't forget the tools you need to change those.

Remember, when you ascend or decent a ramp, ALL of the weight of the entire trailer is briefly on the front axle as you crest the top of the ramp.

For this reason, DON'T skimp on the axles. Just this short time with all that weight is enough to ruin the suspension of the front axle, as its done over and over again.

Hey Brian, good meeting you at the Miami Show; don't think I've chimed in on the AT forum since.

It's a valid point of consideration, trailer cresting the ramp. But consder the range of loads an axle sees throughout its use. An axle is offered with a particular rating. But at that rating it's also expected to provide a range of motion beyond that experienced just from unloaded to fully loaded. I'm no engineer, and I don't know what additonal range is supposed to be acceptable, but I know it's there. And if we consider that "spring rates" in a trailer suspension are linear, then the additional range of motion in the suspension serves as excess capacity when needed.

To take the hijack to a whole 'nuther level, hypothetically:
Put a 7k lb load on a tandem with 3500lb axles and a 10.5k lb load on a triple with the same axles. Assume the axles have a range of motion capacity of twice the rating. That means that it would take 7k lbs on each axle to fully compress or twist to its design limits.
So when the trailer crests the ramp and all the weight is carried by that front axle what do we have? On the tandem we have a 7k lb load on one axle pushing it to its limit. On the triple, we have 10.5k lbs on that front axle pushing it beyond its design limits. Which one is getting worn out quicker?

Another tidbit relating to tires. Just because you have say 3500lb axles on the trailer, which typically comes with tires rated for 1780lbs each, doesn't mean you can't use tires with a higher rating. Yet another margin of safety to consider.

Holy crap Micheal; get all fricking 'CigDaze' on us!!! :readinghelp: :D :D

I definitely agree with you.

My old setup was a 26' Sonic that weighed in at 7280 lbs. It was on POS (!!) Rocket Trailer with a pair of 3500 lb. axles. Both axles had bent spindles, (one on each side) when I took ownership. I had to replace both axles, and the only parts available without re-engineering everything were 3500 lb. axles. I replaced them with entire new axles, and was much more careful about how I towed, what I drove over (we've all had to hop a curb with the trailer before), and specifically how I crested ramps; at an angle when possible.

The trailer lasted for a LONG time just fine after that, and is still in use today several years later as I rebuilt it.

I should have been more specific above, that it was not necessarily the suspension that has issues but it would be other the other axle components, i.e. spindles, lugs, and bearings.

:D
I know, I was going to say Nick would be much better at sharing the theory...with drawings and finite analysis to go with. :D

But it's actually something I've been wondering about for a while...the total capacity/range of motion for a torsion axle. I'm sure we can all agree that a tandem dually might be a little too much overkill for a boat listed at around 5k rigged. :D

If you get a replacable spindle spare make sure that the axels have replaceable spindles.