Do trailers with coil springs and shock absorbers sway at higher speeds?

My 2001 Cobra trailer arrived from the previous owner with lead weights and dumbbells at the front to increase tongue weight. I removed them and found still plenty of tongue weight and no towing instability behind a Toyota 4Runner at speeds up to 85 mph (Arizona highway speed!) I replaced the tires last year with recommended trailer tires and have absolutely no problems except in very strong gusty side-winds, when I slow to 70 mph.

I suspect the geometry and suspension of the tow vehicle are an important part of the equation - I have always used robust, heavy four-wheel drive vehicles designed for towing and have never experienced severe instability problems.

Mike

Mike the Strike wrote, On 6/11/2014 6:17 AM:
My 2001 Cobra trailer arrived from the previous owner with lead
weights and dumbbells at the front to increase tongue weight. I
removed them and found still plenty of tongue weight and no towing
instability behind a Toyota 4Runner at speeds up to 85 mph (Arizona
highway speed!) I replaced the tires last year with recommended
trailer tires and have absolutely no problems except in very strong
gusty side-winds, when I slow to 70 mph.

Gulp! _Slow_ to 70 mph? Better check the speed rating on those ST
trailer tires, because the standard rating is only 65 mph! Some ST tires
are rated up to 75 mph, using different load inflation charts (generally
requiring much higher inflation pressures) than the normal ST tires.
Those stiffer sidewalls people like to talk about are intended for
stability, and the tradeoff is they heat up more easily.

Most people don't realize how different ST (trailer tires) from other
tires. They are not "stronger" passenger car tires, or even "stiffer"
light truck tires. They are designed for a specific purpose that is
quite different than car and truck tires.

If you want to tow your trailer at 85 mph, you better get LT (light
truck) tires with the appropriate speed rating (I'd use a speed rating
of at least 100-110 mph), and be sure you have them at the correct pressure.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
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