converting a dual axle into a single axle

[bob johnson]

Well I think I have a need to retrofit one of my dual axle trailers into a single axle. I have a 22 ft starcraft holiday...it is being rebuilt, and I never owned it when it was complete, so I don't know its final weight...but am guessing that it might fall around 1300 lbs...add a 400 lb motor a pair od 60 lb batteries, 33 gallons of gas...maybe 100 lbs of misc gear after that...and I think the rig will weigh in about 2200 lbs... the trailer I bought for it is a 6800 lbs capacity... I think id beat the boat to death..

I have two other dual axle trailers that need work...but the springs I need to buy seem to only come in 1500 lb capacity( 23.5") four of those puts me at 6000 lbs!

one trailer was rbuilt with only one axle but it doesn't run good with the other springs hanging on for the ride...plus everything is rusty...so I am thinking of just taking that axle off and installing a 3700 lb TORSION axle...it will give me the low riding capacity I need for shallow boat launches, plus I don't have to buy springs or shackles or spring hangers..

so my question is just how to mount the torsion axle to the sliding-adjustable part of the trailer that the old springs attached to...

I am assuming the torsion axle just BOLTS straight up to the frame..but in this area there is the slider...do I just remove the slider??? it has about 4 sets of holes for adjusting the position of the axles.

plus ( I cant visualize one) is there any reason a single axle wouldn't work on this big long trailer ??? 25' long


bob

 

[smokeonthewater]

Weld it to the sliders... Then it'll be easily adjustable

 

[bob johnson]

Weld it to the sliders... Then it'll be easily adjustable

I like it!!!!!!!! plus the fenders mount to the slider!!

another question is ,: does anyone think the galvanized 5 X4.5 hubs ( 1-1/16th x 1-3/8ths bearings) will fit on the torsion axle spindles of the same bearing size???


you can see the slider in this photo:

bob

 

[Lou C]

I think is might be a safer bet to go with a 5200 6 lug axle with 15" rims and 12" brakes in case the boat weighs more than what you might think.

 

[smokeonthewater]

If he was gonna do that he could simply bolt on two 2000 lb axles

 

[Grandad]

Hmm.. I can't speak to the economy of your plan, but I wonder at the need to soften the ride. My twin axle trailer was custom built before I purchased it with the boat as a unit, so I don't know the design spec but I'm very happy with the package. The boat is a 21' Holiday 120 HP I/O with 2 deep cycle batteries and an 18 gallon fuel tank. The two axles are each rated 3500 lbs with 14" wheels. Unless the roadways that you trail on are particularly rough or washboard, I would be reluctant to amputate. Having had boats previously on single axle trailers, I've been pleasantly surprised at just how well the twin axle performs.

I'm no suspension expert, but I like how the impact energy of an individual bump gets equalized between the two wheels, dividing the energy and softening the ride. A few weeks ago, I dropped the rear wheels over the concrete edge of a launch ramp that was a little on the shallow side for loading. Had this been a single axle, I might not have been able to pull out, even with the bull low 4 wheel drive of my Explorer that I resorted to. Are you sure this amputation is a good idea? - Grandad

 

[Silvertip]

If the tongue weight is correct as the trailer sits with the tandem setup, conversion to a single axle would mean the new axle needs to be installed where the center hanger is. Installing the single axle where the front axle is makes the tongue too light. In the back position makes it too heavy on the tongue. I too would not alter a thing until you're able to test drive the rig as it is.

 

[smokeonthewater]

Judging from his pic I'd say "as is" would yield a very poor ride.

 

[Government cheese]

Don't forget the weight of the trailer.

 

[lckstckn2smknbrls]

Couldn't he remove a few leafs from the spring pack?

 

[smokeonthewater]

Or simply buy 1000 lb springs

 

[lckstckn2smknbrls]

Or simply buy 1000 lb springs

In the OP's first post he states he can't find lower rated springs.

 

[smokeonthewater]

He hasn't looked in the right place

http://www.etrailer.com/Trailer-Sus...tml?feed=npn&gclid=CLOb8JTGnMcCFYsDaQodv_4LmQ

 

[lckstckn2smknbrls]

Wrong length.

 

[smokeonthewater]

That was just an example... There are lots of springs out there and if length is an issue it's fixed easily by moving mounting points.

That said, he already said he wanted to use a single torsion axle.

 

[lckstckn2smknbrls]

Wrong length.

My mistake.

 

[bob johnson]

Hmm.. I can't speak to the economy of your plan, but I wonder at the need to soften the ride. My twin axle trailer was custom built before I purchased it with the boat as a unit, so I don't know the design spec but I'm very happy with the package. The boat is a 21' Holiday 120 HP I/O with 2 deep cycle batteries and an 18 gallon fuel tank. The two axles are each rated 3500 lbs with 14" wheels. Unless the roadways that you trail on are particularly rough or washboard, I would be reluctant to amputate. Having had boats previously on single axle trailers, I've been pleasantly surprised at just how well the twin axle performs.

I'm no suspension expert, but I like how the impact energy of an individual bump gets equalized between the two wheels, dividing the energy and softening the ride. A few weeks ago, I dropped the rear wheels over the concrete edge of a launch ramp that was a little on the shallow side for loading. Had this been a single axle, I might not have been able to pull out, even with the bull low 4 wheel drive of my Explorer that I resorted to. Are you sure this amputation is a good idea? - Grandad

the rating on the axle(s) is not an ISSUE, it is the rating of the springs!!!!!!...two 3500 lb axles does not , a rough ride make!!!!!!!! BUT two sets of 1,500 lb springs does!!! I wouldn't buy an axle rated at less than 3,000 lbs....not mater how light the springs! 3500 seems to be the most common anyway. I only looked at one source for trailer parts. this one site I use seems to always be the best for prices and availability. I guess I could look elsewhere for lighter springs to keep the trailer a dual axle...BUT.... I REALLY like the low slung weight feature of torsion springs!!!!!!!! it puts the boat 8" or more closer to the ground than standard a springs set up, all other things being equal.... less stuff to rust away and squeak, .....that's one reason I was looking to go to torsion spring axle.