trailer wants

[floater212]

I have a 2005 rinker 212 captiva 20.5 foot boat with a " heavy single axle" set up, what would or even could I do to make it a dual axle? How can I get it centered and what do you measure off of to keep it square? the boat is about 3500lbs. empty, I was thinking a dual setup would pull better than the single. should I get same weight axles or get lighter ones since it will be 2 axles? As for wheel and tires? it has 6 lugs on the single with 10 ply tires that need 80psi cold, how would I figure that out too? It just feels so heavy while pulling down highway.

 

[Silvertip]

Adding an axle, two more wheels & tires, springs and hardware isn't going to make it any lighter. What are you pulling this rig with? You may want to spend the money on the tow vehicle if the rig seems to much of a load. Unless you have access to a welder, grinder and a good assortment of tools you can't do a tandem conversion in your garage. New spring hangers and center pivot hangers need to be added. This is not a bolt-on conversion.

 

[floater212]

2012 f150 truck to pull it, it just feels heavy, it tows straight, rides ok but any bump and it feels as if the trailer will pull off receiver hitch. the 21' boat, to me, is too heavy for a single axle, I've seen more dual axles on other 21' ers and had 3 blow outs in one year with 10ply tires, maybe too hot so axle is under sized... just looking for ideas. I have been looking at welders too..lol

 

[airshot]

I agree with SilverTip....not worth the trouble, to add another axle... look into better tires if the capacity of your trailer is adequate....

 

[Alumarine]

What is the capacity of your current axle?
If it doesn't "feel" right, maybe the tongue weight is incorrect?

 

[tpenfield]

Assuming that you have a single 5,200# axle . . . You could go with two 3,000# axles and get a bit more capacity without being overkill. Surge brakes, if you currently don't have any brakes.

 

[briangcc]

In the long run it may be a wiser move to simply sell off the single axle trailer and put the proceeds towards a tandem.

It's still not going to feel any lighter and may actually feel heavier due to the added weight of the tires, rims, axle, springs, etc.

Having owned both, a tandem seems to do better in cross winds (ie when being passed/passing semis) and is a bit more forgiving when backing up as it takes a bit more effort to get it to turn. But bump wise, it's going to be the same.

Are you sure the issue just isn't with a loose drawbar in your hitch rattling around when you hit bumps? I've had that happen in an Acadia and to a lesser extent a 4 Runner. Sounded like something was going to fall off every bump I hit.