How do I level boat/trailer with tow vehicle?

[Rookster]

Hi All,

Newcomer to iBoats and loving the online environment! Question about towing a boat. When I had my single axle pop-up trailer that I towed with my minivan, the trailer always made the back of my van sag low. Could never figure out why since I constantly saw other vans like mine pulling heavier camper trailers with no sag at the rear. I tried installing airbags in the van suspension springs which helped a bit but not much.

Fast forward to a boat I just bought and plan to tow with a new SUV of the same tow capacity limit as my van, but boat and trailer together will weigh in much closer to that tow capacity limit.

Could it be as simple as buying the right height hitch so that the ball is raised and level with the receiver of the boat trailer - when the boat trailer is sitting level?

http://ststatic.blob.core.windows.n...class-iii-fusion-trailer-hitch-ball-mount.jpg

 

[robert graham]

I tow my boat with my Buick Roadmaster....fairly heavy tongue weight, so I have air shocks installed....run about 140 PSI while towing, let out a few pounds while not towing so back of car don't sit up too high and car rides rough.....maybe 100-120 PSI for non-towing....The air shocks work great and rig sits level during towing....2 air shocks installed about $200....

 

[Rookster]

Thanks. That was my first thought. I had air shocks on my minivan for towing camping my trailer - could never keep them at the same pressure...think one leaked. And it costs $350 here in Ontario on the north side of the border.

Still wondering about a raised hitch to prevent the tounge from coming down too much onto the hitch...less weight?

 

[Silvertip]

You are looking at this as ONE problem which it may be -- but there are TWO issues you need to address. 1) measure the distance from the hitch ball (top, bottom or middle) to the ground. 2) Determine the tongue weight of the trailer using a standard bathroom scale. That weight should be 10 - 15% of the gross trailer weight (boat, trailer, and everything in it). 3) If tongue weight is too high, move the boat back on the trailer. If too low, move it forward. 4) With tongue weight properly set, attach the trailer to the tow vehicle. 5) Now measure how much the vehicle squats (subtract the second measurement from the first). An inch or two of squat is acceptable. More than that will require some suspension help on the tow vehicle. 6) If there is just an inch or two of squat, see if the trailer is level. If the tongue is down, add a hitch with an inch or two of rise. If tongue is high, add a hitch with an inch or two of drop. It is not essential to have the tow vehicle level unless squat is so bad that the suspension bottoms out on even moderate bumps. That can only be helped with suspension modification such as air bags or air shocks. Obviously if they are leaking they are of no help. You also don't want air adjustable devices aired up so high that the vehicle rides like a lumber wagon.

 

[Silvertip]

Thanks. That was my first thought. I had air shocks on my minivan for towing camping my trailer - could never keep them at the same pressure...think one leaked. And it costs $350 here in Ontario on the north side of the border.

Still wondering about a raised hitch to prevent the tounge from coming down too much onto the hitch...less weight?

A raised hitch does not reduce the weight of the tongue on the back of the vehicle. It just raises the tongue. See may response above.

 

[Rookster]

Supremely helpful - thanks a mil'...I will follow these steps (next month when I get the rig in place) and let you know how it goes!

 

[jkust]

Sounds like a case of way too much tongue weight. I will say that I had a 4000+ lb trailer way back in the day towed by a minivan for a summer that had the factory air springs and onboard compressor that would keep it level no matter the weight. The only time the van ever sagged is when I brought home a full ton of landscape bricks in the van which completely overpowered the springs. Fast forward to today and my current trailer is 6000lbs and tow with a body on frame suv very close to the max capacity also with factory air springs and onboard compressor and again you can clearly see how well the system keeps the rear end level helped along by the proper weight distribution on the trailer and hence the tongue.

 

[Rookster]

Speaking of tongue weight, is it usually possible to adjust? Would it be done by how near or far the boat is placed on the front of the trailer? Seems like a real guessing game to find the right location as the boat can only be moved back and forth on the trailer during loading in the water (or with a boat lift!), unless the trailer has rollers...curious to know what everyone thinks.

 

[Rookster]

2) Determine the tongue weight of the trailer using a standard bathroom scale. That weight should be 10 - 15% of the gross trailer weight (boat, trailer, and everything in it). 3) If tongue weight is too high, move the boat back on the trailer. If too low, move it forward. 4) With tongue weight properly set, attach the trailer to the tow vehicle.

Apparently no less than 60% of the boat's weight should be toward the front of the trailer, and no more than 40% at the back...if that's true, could it limit the extent to which tongue weight can be adjusted?

 

[bruceb58]

Fast forward to a boat I just bought ...

So you did buy a boat...what did you end up getting?

 

[Rookster]

Lol - I wish...nope, nothing brought home yet. Still too cold. Can't hit the water in May, but when I do I'll be sure to let everyone know!

 

[frantically relaxing]

Apparently no less than 60% of the boat's weight should be toward the front of the trailer, and no more than 40% at the back...if that's true, could it limit the extent to which tongue weight can be adjusted?

To clarify, change the word "trailer" to "axle(s)"..

it a simple matter of moving the boat, and/or moving the axle if just moving the boat wont' get you there...

 

[Illinoid]

The axles on my pontoon trailer were easy to move forward or back, I just loosened the bolts and used a come along to move them back and just used the winch on the trailer to move them forward.

 

[Rookster]

Nice! Hope the Bowrider axles work the same way!

 

[Blind Date]

2) Determine the tongue weight of the trailer using a standard bathroom scale. That weight should be 10 - 15% of the gross trailer weight (boat, trailer, and everything in it).

A singe axle boat trailer should have 7-8% of the total weight on the tongue. With a tandem you only need 5% .

[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]STEP #3: Figuring Tongue Weight... is important because too little will cause
trailer sway and too much will cause uncontrolled "pushing" of the tow vehicle.[/FONT]

[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]A.[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Transom should be flush with the end of the bunks/rollers to make sure that tongue weight calculation is correct.[/FONT]
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]B.[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]To determine proper tongue weight, total the package weight (boat with fuel/battery, motor with maximum horsepower, and trailer) and multiply it by 6% on single axles and 5% on tandem axle trailers. ShoreLand'r suggests that tongue weight may be acceptable in a 5-7% range.[/FONT] [FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Example:[/FONT]

[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Boat with fuel and battery[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]2,000 lbs.[/FONT]​
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Motor[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]500 lbs.[/FONT]​
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Trailer[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]900 lbs.[/FONT]​
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Total Weight[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]3,400 lbs.[/FONT]​
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Single Axle Figure[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]x 6%[/FONT]​
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Tongue Weight[/FONT]	[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]204 lbs.[/FONT]​

 

[Rookster]

Excellent chart and info...thank you! EZ load trailer would seem to be way more adjustable than one with no rollers I guess.

 

[Rookster]

No Title

Seems to be adjusted properly right out of the gate - when I picked it up, my tow vehicle dropped only half an inch...performed really well, way better than I feared! Thanks for all the advice.

 

[ezmobee]

Yeah, that looks real good.

 

[fhhuber]

when tongue weight is causing the tow vehicle to "drag ass" you may need to use a heavier tow vehicle ... AND might need an "equalizer" hitch system.

http://www.reeseprod.com/products/weight-distribution/strait-line/xDqAUvNOHeKtsUlhKkqrPpp1KSMoYS1U
One of the spring loaded equalizer systems.

By use of springs it acts on the FRAME of the tow vehicle to apply part of the tongue weight to the front of the tow vehicle.

A frameless (unibody) vehicle can be bent by these hitches.

 

[fishin98]

Looking at the picture, you are good to go. When loading gear in the boat and vehicle, pay attention to spreading the load evenly.