Towing over width

SCORPIO

Well-Known Member
Apr 7, 2008
2,742
Delaware
Boat Info
1989 300 DA
Engines
Twin 5.7 Merc Alpha I
Anybody tow a boat that is over 8'6" wide? I'd like to hear your experiences and advice. I'm planning on bringing my 1989 300DA with 11' beam home for the winter. I purchased a brand new triple axle aluminum bunk trailer as an insurance policy against hurricanes and other bad coastal storms since the yard in my area won't haul you for a hurricane, says you're safer in the water. The other local yard inland sold off their hydraulic trailer so they can no longer pull boats, go figure. Anyway, the recent close call with hurricane Mathew was the catalyst that finally brought me to the realization that I needed a better plan than to just add fenders and cross my fingers. So now that I have the trailer, I'm planning to bring the boat home, about 165 miles, for the winter. I can store it on my property, probably indoors, and will do a lot of projects I've been putting off due to distance and time constraints. I know I will need permits from the two states I will be towing in and I also know I have enough truck to handle the load. What I'm interested in is any pointers/pitfalls that others with similar experiences can provide. Specifically, how stable is it towing a wide load?
Thanks
 
Overwide towing is very doable. I have been doing for more than a decade, and so do many of my friends.

Obviously, you need permits and should be mindful of the laws.

An appropriate tow vehicle and trailer is an absolute must. Beyond that, you need the right hitch, and proper weight distribution.

You asked specifically about stability. That depends entirely on the above. I tow with a single wheel '01 Ford PSD. I use a weight-distributing hitch, 12ply trailer tires, 10ply truck tires, and 7Klb electric brakes on all three trailer axles. You will be a good bit lighter than me, especially with that aluminum trailer. Is that a fixed-bunk aluminum trailer, or adjustable?
 
Height may be a limiting factor. Besides that, travel il at off peak times, with the proper permits and if required, lead and following vehicles. To echo Keokie, With the proper vehicle and trailer, towing a large load is far easier than a smaller load.

If if this is a more than a one time thing, one winter project to consider is a hinged arch.

Good luck.
 
Some of the things mentioned above might not be needed. An example--pilot vehicles are only needed on secondary roads, not on a freeway for a boat the width of yours.

You can buy your oversize load permits on line in many states and many states have annual permits, not requiring a permit for every trip.

Put orange flags on the widest part of your load, have your "Oversize Load" signs front and rear. Also, the comments above about towing only during certain times may not apply. In all of our state (WA) the only areas where times are restricted are around Seattle and the burbs.

If you plan your tow, do your homework ahead of time, abide by the requirements and take your time, towing that size boat will be a breeze.
 
Thanks guys, that reassurance is very comforting.
A few more details on my rig: Tow vehicle is a 2011 Ford F250 4x4 PSD Super Duty crew cab with 8' bed with Firestone airbags. I'm getting and upgraded hitch, probably a Reese Titan, rated for 18,000 lb weight carrying with a 2000 lb tongue weight.
The trailer is a 2017 Venture tri axle bunk trailer with disk brakes on all three axles, and a 12,000 lb electric winch. The bunks are adjustable also. Trailer is rated for a load of 12625 lbs with a GCWR of 14625, which should be plenty as my dry weight is 9800 and I will have no water, waste and only a partial fuel load. I also will be unloading a decent amount of my gear (tools, spares, anchors and rode) prior to the trip home. I will measure the boat on the trailer for height but I think I should be below 13'6" but will verify. I may have to lay may arch back to gain clearance, we'll see.

I'm in the process of setting up the bunks and find I may need to slightly modify the outside mounts to gain a few more inches of width to clear my inboard lifting strakes. Shouldn't be too much of a problem, just takes some time.

I see BoatUS has a discount on permits through Mercury permitting, may check into using that service. In checking the laws in DE and PA, the two states I'll have to get permits for, it doesn't look like I'll need a pilot car at all. There are a few restrictions like daylight only and no holiday towing, but that shouldn't be any problem. It's going to be about a 4 hour trip +/- so I can time it to miss most of the traffic spots.
 
You have plenty of truck. Make sure to get the boat positioned correctly for proper tongue weight. A weight-distribution hitch can add a lot of stability. However, they often don't play nice with the tongues on aluminum trailers or surge brakes. With modification, you can't solve both.

Are your discs surge or electric over hydraulic? If they are surge make sure to have a mechanical or electric lock out for backing up.

Don't forget good tie downs, and inflate tires to their maximum rating. As an aside, I have bias ply light truck tires on my trailer. Radials do not do well with multi-axle heavy loads.

Keeping an override in a narrow lane can be challenging at times. I have learned to center the truck and trust the trailer. You will notice that 11' beam will take up all of most lanes.
 
Thanks for the tips Keokie, they are much appreciated. The brakes are surge disks with a pin for lockout. Tires are bias ply I think. Trailer manufacturer doesn't recommend weight distribution hitches due to aluminum tongue. That's why I want to upgrade my hitch for higher load carrying. I must admit to being a bit apprehensive about all that width and being passed by big rigs. Going to be taking it slow and easy.
 
A classV hitch with a 2.5 inch receiver will allow you to run a solid steel 2.5 inch shank. I'd recommend a goose neck hitch ball. You can get a 2 and 5/16 rated at 30k pounds. Is the trailer torsion suspension or leaf spring?
 
It's leaf spring. Good idea on the goose neck ball. Going with a solid drawbar for sure.
 
My experience has been leaf spring trailers are preferable with very heavy loads.
 
Since it sounds like you already have the trailer,this question doesn't apply, but I'm curious: Can they be bought/made as a 5th wheel type set up instead of on the hitch? Gets the weight on the truck axle instead of behind it? You can tow more weight that way too. Towing a heavier 5th wheel is easier than towing a lighter travel trailer, even with weight distribution hitches.
Mike
 
I don't know the answer to that one but I've thought about it myself. Surge brakes would be out but electric over hydraulic would work.
 
IMG_0062.jpggooseneck trailer tows very smooth. Get your over width permits.
Put your right trailer wheel on the white line, figure out where your truck is on the road and drive.
 
Yes, you can get a fiver trailer made for boats. A buddy of mine tows a 2003 340 on a 5er made to fit 2 three person pwd's in front of the boat. The trailer has 4 axles and brakes on all wheels. It is hard to make a 5er boat trailer out of aluminum. The only ones I have seen have the gooseneck portions made from steel.

Tags definitely don't pull as well, but boats tend to pull better than box trailers. There are several reasons for that. The most commonly stated is aerodynamics. However, boats have more weight in the stern which allows trailer axles to be moved rearward, and still maintain proper tongue weight. This helps with stability.
 
Don't forget your safety kit for the truck with the usual assortment of tools (including a portable impact wrench), flares, bottle jack, grease gun, temperature reading gun (for checking trailer wheels/axles/tires), kneeling pad, rags, spare coolant, brake fluid etc.
 
Scorpio,

You won't have any problem with that combination. My overall height is 12'6" and that's to the top of the light on top of the arch. I could give you a measurement from the ground up to the bottom of the hull to give you some way to gauge where yours might sit. I have towed mine since we bought it 11, years ago all over Eastern Washinton, Northern Idaho and to the San Juans and back and the boat isn't the problem, it's the other idiots on the road! LOL!!! I wasn't able to travel at night in Idaho but I can in Washington and have everything to do so, but have elected not to. That day will come I'm sure.

What I HAVE noticed is that since the saddle tanks are at the very back, towing with a full load of fuel can cause a little sway. It's worse if there is wind, two lanes roads with trucks coming from the opposite way or while headed downhill. Most of the time just slowing down a smidge helps. The towing speed in Washington is 60 mph and I NEVER (Well usually!) exceed that. I just try to blend in with the big rigs and hope to keep the middle finger exposure of other drivers to a minimum!

Having the 300 DA on a trailer opens up so many more places to go boating for us. When we lived in Spokane there were many lakes to choose from each weekend and the San Juans' in July for a couple of weeks. Living in Prosser allows us to choose which part of the Columbia or Snake river we want to explore and we still have a bunch of lakes to choose from including those in Northern Idaho. I also like having it at home to do various projects including cleaning and waxing. I have it parked inside and don't need to winterize it, but I usually do. It stays cleaner and the sun isn't beating down on it when it's not in use.

I do need to do some work on the trailer and might PM you for some info and price!! Mine is a home made trailer, with electric brakes all around. I tend to chew up tires and replace them about every 4 or 5 years. When I think they can go 6 years, they let me know! I blew a middle tire this year that was in it's sixth year. I figured they don't get much abuse being in the middle and tried to stretch those two tires a year past the other 4 tires. That didn't work! I'm an expert and have changed more tires on the boat trailer than I have on all previous vehicles up to this point in m life!! I think I've changed 5 in 10 years!
 
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Sundancer, how far forward from the transom is your rear most axle? I'm setting up the bunks and tongue weighs and I'm trying to get a feel for where the axles should be located. As you stated, the gas tanks as well as both engines, outdrives and batteries are all located in the first six feet or so from the transom. I don't want to have too little tongue weight from the axles being too far forward, conversely, I don't want too much tongue weight either. That and I don't want to over load the front or rear axles much.
Do you happen to know what your boat weighs as it sits on the trailer? I don't plan to have any water or waste in the tanks and I'm at about a half load of fuel right now. I will also remove a bunch of our gear from the boat prior to the tow home in order to keep weight down. Also, about how much weight do you have on the tongue? I've seen recommendations as high as 15 percent and as low as 5. My trailer manual mentions 5-10 percent. I'd like to have some idea of what that number is going to be. I have a tongue weight scale on order from etrailers so I will be able to measure it accurately but don't have a clue as to what I should be looking for. If she weighs 14,000 on the trailer, I'd guess 700-1400 lbs. All depends on the gross weight. Thanks for the driving tips, I'll be sure to keep them in mind while doing the trip.
 
I trailer my 300 weekender. Biggest problem for me was getting it on the trailer. Don't back too far in the water. I found it is easier to back the trailer in the water just enough to pull the bow of the boat into the center bunks (I use a dock line running through the eyelet for the anchor rode, it helps keep the boat centered) then have the truck driver back in the water as I walk the boat up onto the bunks and onto the bow rest. A shallow not too steep ramp works best. Be very careful as you pull the boat out of the water because the stern will settle on the trailer and tighten up the bow winch strap. You will have to release tension on the winch as the boat comes up the ramp or you risk pulling the bow eye out of the boat (don't ask how I know). I have my bow stop about 9 to 12 inches farther forward than it looks like it should be because as the stern settles on the trailer the bow pulls away from the bow stop (think angles and geometry). On a shallow ramp my bow may be a few inches from the bow stop when the boat is out of the water, the steeper the ramp the farther the bow will come away from the bow stop. Don't even try winching the boat back to the bow stop, you will pull the bow eye off, at 10,000 lbs. that boat won't move. My props are always just aft of where the bunks end (shaft drive). You will be able to figure out how far to pull the boat onto the trailer by observing where the curve of the bow sits in the center bunk. We can load our boat in about 10 minutes.
 
Thanks vanman. Let me be sure I understand what you are saying; If I pull boat up to bow stop with stern still floating, as I pull up the ramp and she settles onto the bunks, the bow will pull away from the bow stop, correct? Have you ever weighed your boat on the trailer? Got any ideas on tongue weight? You are saying you have your winch post farther forward to allow for settlement? So you pull her farther on and let her settle back aft as you come up the ramp, is that right?
 
You got it right. Never weighed the boat and trailer. The boat doesn't really settle back aft (move) it just sets down where it sets down. I don't know how much tongue wt. I have, you can tell when you are towing if your boat is too far back on the trailer. It took me a few tries to find the best spot to pull the boat on the trailer far enough. Like I said for me I put the curve of the bow in about the same spot in the center bunk and I is always pretty close to where it needs to be, with that long of a boat and that weight I find it doesn't have to be exact. I might take a couple of pics if interested.
 

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