How much is too much tongue weight on a single axle?

[reeman]

I have determined that my average level state tongue weight is 400lbs. To me this seems a little high on a 3850 gvwr single axle rig. I do use an eq hitch so that does decrease the load shocks somewhat but I would like to bring it down a little just the same if at all possible.

I will be checking the frame deflection on the A frame to see exactly how much it has bent over the past 7 years of light use and posting the results to this thread.

Anyone else that has a lippert setup with the short a frame to a single axle 21'6" please let me know if they have had frame deflection issues in the past with either their minnie drop or winnie drop single axle.

[Ray,IN]

The usual figure is 12%-15% of ball-hitch trailer weight for best towing, 10% is the minimum safe ratio. Yours figures come out to 10.3%

[reeman]

Originally Posted by Ray,IN

The usual figure is 12%-15% of ball-hitch trailer weight for best towing, 10% is the minimum safe ratio. Yours figures come out to 10.3%

I do find that the a frame looks a little bowed up. It may indeed have been heavily front loaded by the previous owner unfortunately. For that matter they may have loaded it really heavy and pounded it down the Bamfield road quite a few times to China Creek. So if it has deflected slightly then that would be the reason.
Could also be a big part of the reason why we only got a few years out of the lippert 3500 lb torsion axle.

My main concern is that now the trailer is lifted to a sensible clearance level and the axle has a better spec for the 3800 gvwr the teeter totter load shock effect increases proportionally even if we only load to no more than 3100 to 3200 lbs including the hitch weight.

Either way it is time to rent a scale instead of having to use the public ones that are prone to getting broken all the time by smokey and the bandit style clowns hitting the brakes under load or driving over it when closed way too fast.
PS I did correct the stats to 3800 gvwr. I have read somewhere that the a frame is max rated for 5000 because it is a 2 inch ball setup and the maximum load is 10% of the frame rating. It would be a mistake to max the forward weight to 500 lbs but I do have some wiggle room if I move the batteries slightly and then put on 2 twenty pound propane tanks.

[k.darwin]

Hitch weight should be 10% to 15% of actual trailer weight. How much weight is actually on the axle? With 400 lbs on the hitch, I'd expect the axle to be carrying about 3000 - 3600 lbs.

Be careful with WD hitches on single axle trailers. The WD hitch transfers weight from the hitch to the trailer axle and if the trailer axle is already near it's capacity you can push it over.

[reeman]

Originally Posted by k.darwin

Hitch weight should be 10% to 15% of actual trailer weight. How much weight is actually on the axle? With 400 lbs on the hitch, I'd expect the axle to be carrying about 3000 - 3600 lbs.

Be careful with WD hitches on single axle trailers. The WD hitch transfers weight from the hitch to the trailer axle and if the trailer axle is already near it's capacity you can push it over.

Thanks again @k.darwin

Our trailer usually axle loads at just over 2900lbs so the WD hitch is a little bit of over kill loading on our SUV but is fine on our full half ton pickup.

I am in the process of taking the AGM batteries off the hitch and putting them in a spot where their 140 lbs of weight will balance the extra 195 lbs on slide out side that this trailer comes with stock from the factory.

As it is there is 195-200 lbs of difference side to side straight from the factory. Which is fine if the trailer is loaded heavier on the passenger side than the drivers side to compensate for the factory design difference on the single axle. But not if the hitch is overloaded with the batteries and propane, as ours is.
Putting the WD hitch on does put about 50 lbs of extra weight on the A frame connection to the trailer frame proper so it needs to be used without too much torque down on the frame connection.

If the WD puts more than 100 lbs forward while sitting level then it may indeed cause issues in the future. However the trailer frame A frame is not bending more than it was when we purchased it with the cheap lippert axle warn out. Using a WD hitch is not showing signs of causing serious issues as of yet. If using a WD hitch does start to cause more frame bend, we will take it into the highly professional shop that replaced our worn out cheap lippert torsion axle and have them inspect and reinforce and the A frame and connections to the frame. The quality of their work is second to non here in Victoria.

Hopefully we will get a few more years out of the trailer without it winding up in someones backyard as a guest cottage, as most cheaply built single axle drop style trailers do in British Columbia!

Driving up in the interior of BC one can tell the best farm neighbourhoods because there are at least one or two trailers parked in the field being used for migrant farm workers.