Tongue weight on trailer.

CatMar II

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We have a 1983 Tarpon. Looks just like the Tournament. My question is this. I have a lot of weight on the tongue when trailering. This boats weighs nearly the same as a friends boat. I have no issues pulling his (boat) with our Jeep but when I pull mine it really lowers the back of the jeep. I can either move the boat back on the trailer or I can move the axel forward. I think moving the axel forward is the answer. Has anyone moved their axle and how hard is it? I have a standard Cox trailer. I tried to put a picture up boat I can't figure it out.

Thanks, Rick
 

wspitler

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A good rule of thumb is 10% of the trailer gross weight (boat + trailer) is what the tongue weight should be. 6000 lb trailer then 600 lb tongue weight. Moving the axle up shortens the effective length and may reduce lateral stability. Longer trailers tend to be more stable, back easier and are less likely to jacknife. Too little tongue weight is unstable also.
 

onoahimahi

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You can run a little less tongue weight than 10% if you want - the E-Z Loader manual specifies 5-10% of the total boat+trailer weight. I split the difference and use 7-8%. You can use the trick to measure it with your bathroom scale:

http://hildstrom.com/projects/tonguescale/index.html

They used a 4:1 ratio but you can also use a 3:1 ratio.

-Scott
 

lgusto

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Having hauled lots of very heavy things for years, most non-boat trailering advice I've heard suggests 10-20% tongue weight. I can't see why boats should be any different.

Being ever so detail minded when it comes to my boat, I calculated the tongue weight as follows:

1. Weigh tow vehicle alone
2. Weigh tow vehicle with trailer/boat attached but not on the scale
3. Weigh the whole vehicle/trailer/boat combination

With those three numbers you can exactly calculate your total and tongue weights. I used a local transfer station scale which claims to be accurate to 20 pounds.

In my experience, balance is key. Too much tongue weight and you seriously alter the handling and braking of the tow vehicle and destroy your trailer tires (if dual axle). Too little tongue weight produces a dangerous trailer sway at speed. With my boat and dual axle trailer, 15% is too much. Down around 12% seems best.

I found these guys to be pretty knowledgeable: http://www.sherline.com/lmbook.htm#refrn9

RECOMMENDED HITCH WEIGHT PERCENTAGES

TYPE OF TRAILER

PERCENT OF WT. ON TONGUE

Single Axle

10% minimum/15% maximum

Tandem Axle

9% to 15%

Travel Trailer

11% to 12%

5th Wheel

15% to 25%

PLACING THE LOAD
 

onoahimahi

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Boat trailer manufacturers seem to be pretty consistent at the 5-10% level. Here are three:

1. The EZ-Loader:
http://www.ezloader.com/Manuals/ezloade ... Manual.pdf

page 13 says:
"Proper load distribution on your trailer is also very important. Five to ten percent of your trailer’s Gross Vehicle Weight should be supported by the hitch ball, with the tongue level. This is called “tongue weight”. For example, if the GVW of the boat, gear and trailer is 1,500 lbs., the weight on the coupler should not be more than 150 lbs. – or the maximum rating of the hitch [whichever is less] –or be less than 75 lbs. "

2. Loadrite says http://loadrite.com/towing-info.php

"Improper tongue weight on the tow vehicle hitch ball can cause loss of control of the tow vehicle and result in serious injury, property damage, or even death. Depending upon trailer model, proper tongue weight should be adjusted to 5% to 7% of GVWR when fully loaded."

3. Venture Trailers:
"A minimum of 5% tongue weight and a maximum 10% tongue weight of the trailer GVWR must be positioned over the hitch ball. The Trailer tongue should be parallel to the ground. Too much weight can cause premature brake actuation and loss of control of the towing vehicle. To little tongue weight can cause the trailer to fishtail, resulting in loss of control of the tow vehicle and trailer (total trailer weight GVWR includes weight of the trailer plus load)."
 

81Malibu

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I just bought a tarpon as well. The previous owner had the tongue way too light. On the way home the thing was swaying side to side so much I thought it was going to pull me off the road. I remember having a similar issue with another boat I had and I just played with the positioning till it felt right.
 

Curmudgeon

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Weight the boat and trailer. Any truck stop will allow you to pull on the split scale and give you a weight for the front dolly and the axle, only then can you know. The easiest way to reduce tongue weight is to move the boat to the rear, but advisable only if there will be adequate support for the transom ...
 

CatMar II

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Thanks for all the input. I took it to the local transfer station. Looked good towing a boat in Maine in winter. I am at 24% on the tongue. I then went to a local marina and measured other boats that were roughly the same size and I think I will move the axle.
 

grady23

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Keep us posted on the axle change. I have a '97 Gulfstream and it took me the better part of a full day loading, un-loading and re-positioning the boat till I got the right setup. Trailer tows at 75+ with no problems. You mentioned that you have a Jeep. I've found over the years that vehicles with a short wheelbase are much harder to balance then a long wheelbase.