Trailer Tire upgrading need suggestions

[jstatham]

Hello everyone I have a 1988 24 ft Tracker Party Barge that sits on a Tracker trailer made for a 22-24 ft boat. My pontoons hang off roughly 2 ft off the end of the trailer. This is the original trailer purchased with the boat. I am about to completely redo the trailer and I am wanting to upgrade from the 10 inch fat wide tires to some real 15 inch heavy duty trailer tires. I basically have purchased everything to convert from single 2500 axle to tandem axle 2500 lb axles and add electric brakes. I know this is way overkill but I pull the boat 4 hours up and down mountains and we like to load up the pontoon with all our gear. So here is my issues #1 right now as the boat sits on the trailer with the 10 inches tires I have to backup my Tahoe until the muffler is in the water to get the boat off the trailer. If I add the bigger tires I am going to have to go even deeper so I thought of extending the tongue about 2 feet which should help with having to backup so deep. Unfortunately all the ramps at the lake are not very steep which seems to be the main issue. The boat is basically sitting perfectly balanced on the trailer and there is almost zero tongue weight. In fact when I tow it I have to move cargo to the front to give it some weight so it want sway. I guess the main issue is if I add 2 ft to the tongue is it going to mess up the center of gravity? I originally thought of putting the center shackle right were the original axle was located but with the added tongue length is this going to throw off the center of gravity? Do you think I am completely nuts for adding tandem 15 in tires for a pontoon boat? The reason I want to go so big is one time we had the boat overloaded and had 3 flats coming home and only 2 spares and don't want to ever have that happen again. If you can think of any problems or anything I am missing please let me know.

 

[oldjeep]

Yes, you are nuts for switching to 15" wheels. Stick with tires that keep it at the factory ride height. You can buy 10" tires in an E rating (1,650lbs) So for 4 of them that gets you 6600lbs - that has to be more than double your actual weight.

What is the load rating on your current single axle tires, and have you got them inflated to the max pressure?

 

[jstatham]

I had the 1650 but I would rather have the bigger tires so the bearings aren't spinning 100 mph constantly. It in only going to raise it up less than 6 inches. Is that a big deal?

 

[oldjeep]

I had the 1650 but I would rather have the bigger tires so the bearings aren't spinning 100 mph constantly. It in only going to raise it up less than 6 inches. Is that a big deal?

Sounds like it is a big deal. You are taking an already top heavy tippy load and raising it higher, and simultaneously making the boat impossible to unload without messing with the tongue length. Doesn't sound like an optimal solution. If it were me I would have just bought a tandem trailer that fit the boat and sold the single rather than messing around with any of what you are describing.

 

[fhhuber]

You can figure for every inch higher the boat rides (above ground) you need another 6 to 12 inches of pushing the boat back into the wwater at the typical boat ramp. (some ramps it can mean more than 1 foot per inch of height)

"Not going to raise it 6 inches" means you think its going up about 5... and that means you'll possibly have the rear axle of your tow vehicle underwater to get launched if you don't lengthen the trailer tongue.

Very bad for the tow vehicle.

Just do a youtube search on boat launch fails. There's a few where the whole truck is swimming before the boat floats. Don't be the subject of a new fail video.

 

[H20Rat]

What type of trailer? Scissor or bunk? I suspect bunk, as scissor trailers usually have larger tires already. With a bunk, you may not have the clearance between the tire and tube for a larger tire, especially once the suspension is fully compressed.

In any case, I wouldn't go any larger than absolutely necessary on a pontoon trailer. I've seen a fair number laid over in the ditch taking a nap, just need a strong windy day.

Bigger problem is that you have a trailer that is too small for your pontoon. I'd look for an entirely different trailer first!

 

[smokeonthewater]

First off... the bearing problem you describe is imaginary.... the bearings aren't "spinning at 100 mph" or any other mph for that matter..... they are spinning at X rpm and they are absolutely fine at normal highway speeds for extended periods of time.... taller tires and rims will increase leverage on the bearings from any side loading such as traveling on a crowned road.

Unless you plan to run low profile tires you will be adding more than 6"

Adding the second axle could well be a fine idea IF you are currently overloaded BUT if you are having flat tires due to under inflation, dry rot, or road hazards then you will likely just start having twice as many blowouts and 1 flat out of 4 strands you just as bad as 1 flat out of 2.

You NEED tongue weight.... move the boat forward on the trailer or the axle back.... HINT if you get 10% tongue weight you will reduce your axle and tire weight by 10%....

 

[smokeonthewater]

for reference I estimated your trailer tires to have a 65" circumference (my 8" low pro's have 58" circumference) and at 60 mph your trailer wheel bearings would be turning @975 rpm.... the main and rod bearings in your car should be turning about 1800 rpm and the ball bearings in your alternator should be turning about 3000-4000 rpm

your trailer bearings are FINE!

 

[dingbat]

for reference I estimated your trailer tires to have a 65" circumference (my 8" low pro's have 58" circumference) and at 60 mph your trailer wheel bearings would be turning @975 rpm.... the main and rod bearings in your car should be turning about 1800 rpm and the ball bearings in your alternator should be turning about 3000-4000 rpm

your trailer bearings are FINE!

The dynamic rating of your typically trailer bearing is 7,000+ each at 8,400 rpm. Running them at 975 rpm will hardly get the grease warm

 

[redneck joe]

Not the expert here as i'm just in the middle of my trailer rehab but have learned a bit.



are your current axles sitting on top of your leaf springs or are the leaf springs sitting on top of the axles? If they are like

then you get the full height of the new tires. However if they are below the leaf, and you can flip them to the above, you may not gain anything - but will most likely need to move the wheel fenders up.

 

[oldjeep]

Not the expert here as i'm just in the middle of my trailer rehab but have learned a bit.



are your current axles sitting on top of your leaf springs or are the leaf springs sitting on top of the axles? If they are like

then you get the full height of the new tires. However if they are below the leaf, and you can flip them to the above, you may not gain anything - but will most likely need to move the wheel fenders up.

I sure hope that if he decided to convert a single to a tandem that he bought torsion axles and not leaf springs. Can't say that I've seen a pontoon trailer with leaf springs in 20 years or so.

 

[redneck joe]

ok ignorance here; why not? I've seen (in my recent research) the torsion option but what is advantage and why specifically for a toon?

 

[oldjeep]

ok ignorance here; why not? I've seen (in my recent research) the torsion option but what is advantage and why specifically for a toon?

Height would be the biggest reason. Typically a torsion setup is much lower than a spring type axle - unless you are mounting the axle on top the springs which is a weaker position that relies entirely on the u bolts rather than the axle itself carrying the load of the spring above it.

 

[smokeonthewater]

Balderdash

There is NOTHING "weaker" about the axle being over the spring. The (proper) u-bolts are more than fine for holding the load put to them. Torsion has no functional advantage over leaf springs. Torsion suspension is simple, fast to assemble and attractive and can often be limped home even if the rubber spring is destroyed BUT in a tandem application there are some real disadvantages. The torsion axles are totally independent and as such they don't equalize... if the trailer is even slightly un-level one axle will be carrying more weight than the other which will affect tongue weight and can over load tires. Also on uneven terrain, such as when the tow vehicle is going uphill on the road while the trailer is still going down hill out of a gas station or other driveway, one tire can easily be unloaded or even lifted off of the ground again overloading the tire next to it.

The height of the suspension is also NOT an issue. The height here is from the tires being directly under the pontoons...... If you lower the suspension you will have to raise the boat to keep the tires from hitting the toons.

Of course this assumes that the trailer is currently built right but this is THE reason that pontoon trailers use the 8" and 10" low profile wide tires.

My 48' gooseneck rated for 20,000 lbs has the axles on top of the springs and no problems... pretty sure that setup can work for a little pontoon too.

 

[funk6294]

Why don't you post up some pix so we can see what your working with.

 

[oldjeep]

Balderdash

There is NOTHING "weaker" about the axle being over the spring. The (proper) u-bolts are more than fine for holding the load put to them. Torsion has no functional advantage over leaf springs. Torsion suspension is simple, fast to assemble and attractive and can often be limped home even if the rubber spring is destroyed BUT in a tandem application there are some real disadvantages. The torsion axles are totally independent and as such they don't equalize... if the trailer is even slightly un-level one axle will be carrying more weight than the other which will affect tongue weight and can over load tires. Also on uneven terrain, such as when the tow vehicle is going uphill on the road while the trailer is still going down hill out of a gas station or other driveway, one tire can easily be unloaded or even lifted off of the ground again overloading the tire next to it.

The height of the suspension is also NOT an issue. The height here is from the tires being directly under the pontoons...... If you lower the suspension you will have to raise the boat to keep the tires from hitting the toons.

Of course this assumes that the trailer is currently built right but this is THE reason that pontoon trailers use the 8" and 10" low profile wide tires.

My 48' gooseneck rated for 20,000 lbs has the axles on top of the springs and no problems... pretty sure that setup can work for a little pontoon too.

Weaker in that they are relying on the ubolt and spring plate to carry the load. You don't really see many axle tubes and perches break, you see plenty of u-bolts rust and break.

Interesting, never seen any of those disadvantages on my tandems. And it seems like the only leaf spring tandems I've had were the cheap ones, all of the expensive ski boat trailers are torsion, as is our pontoon trailer. That being said, I don't really spend any time offroading with my boat trailer

 

[smokeonthewater]

I've never had a u bolt break and I didn't say anything about offroading.
If a person lets a u-bolt rust to the point of failure without replacing it then it makes little if any difference whether the axle is under or over the spring.... the pre-load from torquing down the nuts FAR exceeds the trailer weight and the dynamic loads from cornering are also much more than the trailer weight. The price tag on the boat sitting on a trailer does not in any way determine the safety or strength of the type of suspension under it.

Yes torsion axles ARE becoming more common but it has nothing at all to do with leaf springs supposedly being a poor design...

ALSO I didn't say that having torsion axles was a terrible thing. I simply pointed out disadvantages.... I pulled a 45' trailer all over the country for a while with 3 torsion axles under it.... Mostly it was fine but there were a few times tires blew while over loaded going in and out of driveways to make deliveries.

The POINT here isn't that torsion "is the devil" but rather that it isn't inherently better than leaf springs. Both systems have advantages and disadvantages.

 

[funk6294]

Leaf spring suspension has been around forever and a day and proven itself reliable even with the spring mounted under the axle. Jeep as well as many of the oems that still utilize leafs have mounted thier axles in this fashion and I do not recall a rash of axles coming off of these vehicles due to u bolt failure. While torsions are nice and provide some good ride characteristics they lack the ability to distribute the load evenly between axles in a two axle set up, which if the trailer is not loaded dead flat means one set of tires is working harder. Now with all of that said and I know we could keep arguing the merits of either set up but I would be interested in actually helping op figure out how to correct his current trailer dilemma. If he is fairly handy (and it sounds like he might be). He just could be able to correct the issues him self and wind up with the trailer he wants.

 

[smokeonthewater]

But don't take my word for it... check with the professionals.

http://blog.easternmarine.com/leaf-springs-vs-torsion/

http://trailers123.com/leaf-spring-axles-versus-torsion-axles/

 

[oldjeep]

If he is fairly handy (and it sounds like he might be). He just could be able to correct the issues him self and wind up with the trailer he wants.

Possibly, but if his boat is really hanging 2 feet off the back of the trailer then I suspect the only good solution is to get a trailer the right size for the boat. (Regardless of the trailer coming with the boat)