Trailer height....tandem dually vs triple axle
 

Anybody have any first hand knowledge on how much higher the same boat would normally sit on a tandem dually trailer vs a triple axle? I've been looking to upgrade to a 24k GVW 5th wheel trailer and was thinking I'd need a triple axle (due to hieght restrictions) but ran across a tandem dually. For instance, I know my Formula 400SS is about 13' 5" high overall on my current Myco triple axle with the light mast and radar dome stripped off. I have some reference measurements from the guy selling the tandem dually and according to those it appears that the Formula would only sit 1.5" - 2" higher. I had really been thinking that the tandem dually would sit the boat alot higher. Makes me wonder if my thinking was way off or his measurements are way off. Love to just go measure everything in person but the trailer is 1600 miles away. I know some parts of the country it would still work even at 14 ft but in the northeast there's a lot of bridges on 95 that are 13' 7" - 13' 10" so it would not be good if it ended up being 6 inches higher.

There's also a nice triple axle available out in CA that is an option but it's a fixed bunk. This tandem dually interests me because it has the adjustable screw jack bunks (like my current trailer) so it would be a nice replacement for my curent trailer to use for multi boat transport use as well as for my own boat.

Thanks, Pat

Remember that 13'6" is the maximum legal height for a load, i believe nationwide. Also be aware that lots of posted bridge measurements were done years ago, and since they may have added several additional layers of pavement so it could be 6" or more less than posted. I haul heavy equipment and have had some issues due to outdated measurements. As far as the difference in height between the two trailers you just have to know the difference in tire size between the two and if the bunks are the same height above the center of the axle.

Thanks for the info. Ya' I know that 13' 6" is legal height, that's why I'm concerned about the tandem dually. The only point of reference I have to go by is my 400ss on my current Myco triple axle. That is right at 13' 5" to the highest point as it sits right now. With the trailer level and taking a measurement from the ground to the bottom of the V (keel) the info I got on the tandem dually shows that the same area of the boat would sit about 1.5" higher. Ultimately the hieght of the center v-bunks would be the limiting factor, assuming that I don't modify or remove them. After that it's a matter of the main frame rail width on the tandem dually being narrower and higher that the triple axle but there seems to actually be plenty of room there, there's almost 1 ft on the triple axle so there'd still be a few inches of extra room on the tandem dually. My biggest unknown is really that I thought that a tandem dually would put the boat like a foot higher than the triple axle but all the measurements I'm getting are telling me it's more like a couple inches and I just found it hard to believe. I was hoping to maybe hear from someone that actually has one and knows for sure if the couple of inches difference is realistic. In reality it wouldn't be a problem 90% of the time if I'm towing a normal go fast boat but it could limit me on cruisers like my own 400ss, and that would push me to staying with a triple axle.

I've heard the horror stories of guys getting fooled by poorly marked bridges and I don't want be one of them. Generally if I see anything marked at 13' 10" or lower, when I'm towing something that is borderline legal hieght, I try to go around it rather than under it. It makes for lots of exit hopping in Connecticut :)

Thanks, Pat

Sorry for not chiming in earlier. I have a Tandem Dually Myco with solid axles and 19.5 Alcoa wheels with Goodyear commercial tires. It sits higher which is an issue both towing and launching. The keel of the boat sits 29.5" from the ground.

Thanks a bunch for the response here and also the PM. The trailer I'm looking at also has 19.5's so this info is great. On my current triple axle trailer the keel of the 400ss sits at 26". The measurement I got from the other guy on the 5th wheel tandem dually is 28" to the keel of the 46 ft Cigarette that's sitting on it now so your 29.5" measurement tells me that his is probably fairly accurate.

Thanks again, Pat

19.5s is the reason. Trailer would be lower with 16"-17" and low-profile tires. There's a company that makes an extension that runs from the hitch ball to the trailer hitch but I don't remember who it is. At least 6' from what I remember about it. I don't believe it's intended for towing, just install it before launching...

PM waconda. He switched from a Myco trip axle to a Myco tandem dually on his 46 Black Thunder.....after some crappy driver ran into the side of his as he was making a right turn.

Thanks, I will.

Pat

Just a thought. I assume your 400ss has a radar arch that is the tallest point. How about having a setup like my arch does. The rear of the arch has two massive hinges. You remove the front mounting bolts, and the arch folds down.

Thanks for the tip on contacting him, it was very helpful. He confirmed that his boat sits 8" higher on the tandem dually than it did on the triple axle.