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My AV Is Swaying



Here is a interesting one. I have had my AV with a 4" Rancho lift now for about 10,000 miles. After towing my boat up north a couple weeks ago I noticed the trailer swaying back and forth behind the truck and truck has as a sway as well. Since I just put new tires on the trailer, i thought that was the cause. So I stop and reduce the tire pressure in the trailer tires. Seems to get better but still sways side to side when I'm towing. So I think its must be the trailer. So last weeking I am driving up north but this time without the boat. My AV starts to sway when I accelerate or change lanes. Is something lose? The only way I can explain how to simulate the movement is to push on your AV when it is parked from one of the 4 corners. Any Ideas?? :-[
Have you checked the air pressure in the tires on the AV?
The lift kit will really make low air pressure a critical factor concerning sway. Low air gives a lot of sidewall flex.
One thing that can get a trailer swaying is not enough weight on the tounge. Have you changed the balance or load point on the trailer? However, if your Av is swaying without a trailer, that might be the cause of the trailer swaying, but maybe not. Get the Av stabilized, then check out the trailer and work on that if needed.

I second orboater, start with the Av's tire pressures. Get this sway under control.

-- SS
Too much weight on the tongue of a trailer will also cause swaying!
I would have whoever installed the lift check EVERYTHING over. My guess is something is not right with the install. Definitely need to get it taken care of immeditely!!

Good luck,
The correct tongue weight is between 10% and 15% of the total trailer weight (boat + trailer + anything carried in the boat). You can go lower, but sway starts somewhere around 6-8%. Boats are notorious for sway because it is so easy to have a lot of weight in the back (fuel, engine, and that is usually where all to weekend supplies are loaded). The other reason a lot of boats sway is that it is easy to move the boat forward (bow stop) or back and you can move the axles on many boat trailers forward and aft. I have seen 3000+ pound boats with almost no tongue weight - can you say jackknife???

I do agree that the AV should not be swaying, esp. if it didn't before. Tire pressure would be my first suspect, then something lose in the lift kit.

Cheers, Jim
I also have the Rancho 4" lift, and after thinking about it, if the air pressure doesn't solve the problem look at the vertical tie bars in the back end, if those aren't tight or properly installed it will give the springs all the leeway they need to flex side to side.

Just a thought.....
Thanks for all the imput. I am having the guys that installed the lift, it check it tomorrow. The funny thing about the tire pressure. I put 40lbs in each tire and it seemed to get worse, not better. They are Goodyear AT 305 17s. When I lowered the tire pressure to 36lbs per tire it seemed to sway less. Both tests were done without a trailer attached. :cautious:
:B:Speaking of tire pressure---2500 series says 50 psi front--80 psi in the rear tires.never owned a vehicle with that discrepancy???
Check the thread about tire pressure plenty of info in a few threads....set your search for over a 100 days I use 1000 to ensurfe I am at the begininning >:D