swaying

APT wrote:
Far too many assumptions and speculation and other people spending your $$$. $15 for 3 passes at a CAT scale will provide the actual tongue weight and where you stand with respect to all your truck's ratings. Then decide what should be done next.

Do the scale weights with truck and trailer loaded for camping. Depending on location of fresh water tank, your tongue weight can change considerably. My tank is behind the axles, and, my tongue weight can vary up to 200 lbs.

There are several things that can cause or contribute to trailer sway. Your problem could be any one, or a combination of them. Some, you can do nothing about. Most common causes:

1. Trailer is too lite on the tongue
Tongue weight should be 10 - 15% of loaded trailer weight.

2. Hitch not set up correctly
If hitch is not restoring enough weight to front axles of the truck, subconscious movement on steering wheel, oversteering, cross winds, or subtle changes in road surface, can cause sway. If hitch ball is set too high, trailer tows nose up and you have similar situation to lite tongue weight.

3. Unbalanced loading

4. Overloading or soft suspension
If you are close or over your payload, you could have tire sidewall flex or body roll on tow vehicle. Compare loaded weights to payload / GVWR of tow vehicle.

5. Unbalanced or low tire pressure (either truck or trailer)

6. Insufficient sway control
At 35 feet (a lot of sail), a single friction bar may not be enough. An 8000 lb trailer is going to win tug-of-war, with a 6000 lb truck.

7. Strong cross winds.

8. Bad roads.

9. Trailer axles out of alignment.

10. Bad trailer tires.


Scale weights and measurements will tell the story about hitch set up and loaded weights. Measure trailer coupler height (with trailer level) and hitch ball height (with truck level). They should be close to equal as possible. Measure unhitched height of front fender well. With WD, hitched fender well height should be within 1/2 inch of unhitched height.