Certainly not a dumb question at all.
I looked for your original post for a description of the tow vehicle, and
what is being towed (trailer, race car, additional "stuff") and see I
deleted it. The first steps are knowing the tow capacity of your vehicle,
sum of all the stuff that goes into the trailer and the weight of the
trailer itself. Stuff + trailer = GTW (gross trailer weight). TW (tongue
weight) should be around 10% of GTW. Those are general rules of thumb, not
hard facts.
Without a doubt, a class III hitch can be weight bearing or weight
distributing. See http://www.hitchcorner.com/trailer-hitches.htm for some
good examples. A class III maxes out around 5,000 pounds weight bearing,
8,000 pounds weight distributed. A class IV tops out around 10,000 pounds,
12,000 with weight distributed. Another page I found,
http://www.etrailer.com/faq/aboutwd.asp gives a clear explanation of why
weight distributing systems are worth considering. It has less to do with
total weight, althought it does increase towing capacity, as it does with
balancing the load more evenly across all the wheels of the whole rig.
My tow van has a towing capacity of 8,000 pounds. I run it at about 7,000
fully loaded. I chose a class IV hitch because I'd rather use a part at 70%
capacity than 90% capacity for the safety margin. The weight distributing
system is to minimize the effects of bouncing 700 pounds of TW on the rear
suspension, effectively trying its best to lift the front wheels into full
droop. Totally hoses the bump steer of the van <g>. Just for grins I
hitched the loaded trailer with and without the spring bars connected. The
rear of the van was almost two inches lower without the spring bars
attached. The van and trailer ride nice and level with them connected.
In the end, a good weight distributing system will add $300 +/- to the bill
compared to a straight weight bearing setup. Both will happily drag the
trailer merrily along behind your tow vehicle. The biggest difference will
be in stability. I'm just more comfortable saving the dance on the edge for
the track.
John P
From: "Mark Palmer" <mgvrmark@hotmail.com>
Subject: Class III
> So maybe it wasn't such a dumb question after all ...
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