Sway Question

A number have said go to 10ply/load range E tires. Will it work or not... Not positive. I switched from 8ply/D tires on a SW 3500 to 10ply/LR E tires. Being as I only had 55-60 lbs of air in the tires, TBH, I did not feel a difference.
With above said, having just bought my first 15 series truck. XT sizes are now into play, appear to be a pseudo LR C/6 ply tire. will swag any LT style tire will be way better than a typical P metric, or the XT P metric. Tread design can also make or break towing handling too.
I'm in the "I should be able to tow trailer with out bars of any sort shape or form" group. You never know when you can loose or have one loosen up. Best to have a trailer that does not want to "fish tail" sway in its own.
Getting buffeted by side winds, trucks passing or you passing them. Should be expected. Any unexpected movement, should be side to side rocking. Or being pushed sideways as a unit. If the truly move separate, you have a problem. Find the reason, fix it!
You may have too little hitch wieght as mentioned. Too little psi in trailer truck tires for the load. Trailer axles V'd vs perpendicular to travel, not parallel. Too soft a suspension/shocks/tire sidwalls on trailer or TV. Too much wieght on one side of trailer. Hitch mounted nose up. ... I could go on. Hopefully one sees my points.

Marty

Upgrading tires to 10 ply will help a lot. I'm on a much smaller trailer and was surprised how much difference upgrading truck tires did to the stability.

It’s hard to explain to those who don’t have experience towing a lot.
But unless the TT is grossly over or under on “expected” tongue weight, it should pull just fine with a capable half ton.
Salesman wasn’t “totally” lying but also not to be really believed as they’re, well, salesmen.

I wouldn't worry about out of control sway as much as I'd be concerned about the TT and truck not functioning as one. A heavy long TT with a 1/2 ton may not ever sway out of control, but you could experience more than desired movement when over taking a semi, or being passed by a semi and towing in windy conditions. Also it could be a little tense when needing to panic stop on a corner.
Lots of conditions come into play when towing.
Having to keep both hands glued to the wheel with bigger than normal wheel corrections doesn't make for a fun day of towing.
Like I said you may never experience out of control sway, but the day in day out driving experience will wear on you.

The problem is I keep getting different information about sway depending where I look or who I ask. My salesman, for example, told us that the difference between a 28 ft and a 33 ft would not make any difference with sway. Can that be right? I

AS you have surly discovered by now their are many reasons a combo can have sway... so no one fix works on all combinations.

Other expy owners who are pulling the same length trailer can have input for you so check with trailer brand forums also.

One of the worst bumper pull sway incidents I've seen when I was on the road was a one ton DRW truck pulling what looked like a 25-28' TT. We could guess till the cows came in why the combo was swaying.

Some ideas expressed here can add to a sway issue so use proper equipment and hit the road for a short run and see how the combo is working. Then make changes.

Just because you "can", does not mean you "should".

In my tiny situation (20' Nash TT) has an "advertised" carrying capacity of 2000 lbs, problem is after I add the weight for all my "necessities", I can sneak up to the TT's GVWR of 5600 lbs. Especially if my fresh water tank (42 gallons) is filled (an extra 350 lbs).

After I bought my truck in 2005, I weighed my loaded TT at a scale and discovered exactly how the weight was distributed between all 8 tires. You'll be surprised how the weight of beer, food, clothes, full kitchen setup, and other necessities adds up.

Over the years our RV habits and needs have changed and, just like my waistline, I am sure the combined weight of my TT has increased as well--but not over the truck max towing capacity of 9200 lbs.

I parrot the words of others, if you dial in your rig's weight distribution, there shouldn't be any sway issues. I use the plain vanilla WD hitch setup that's rated for 750lb tongue weight.

Over 30' will catch allot of wind, definitely 3/4 ton truck territory for a long drive.

IMHO, ask 10 folks for their opinion and you'll get 12 opinions...

There is a lot to it a not just any single item that folks tend to touch/mention, as it may have fixed it for them.

Towing is a system of many, many components/sub-systems/knobs/dials/etc. Plus many WD hitch systems that all claim to solve sway (most do, but they have to be both sized correctly and the biggie...adjusted correctly)

Many will talk about stiffening the TV's suspension. From higher class tires, to higher PSI, to springs, to everything to do with the TV's suspension. All kinda sorta okay, but most just end up as band aides and not addressing the root cause(s)

Will leave it to the others to advise what worked for them, but note that there has been many newbies lead into circular cycles without resolution.

My advice is first view//read up and learn what sway is. Then what the components & their dials/knobs do.

Bottom line advice is: that the goal is to have the TV's front axle returned to whatever your OEM's manual says. Some talk about front fender height, others to front axle load weight...etc.

Then that the trailer tongue should be in the 12%-15% of the trailer's total weight when loaded.

Finally, that the trailer tongue should be level or pointed slightly down after the complete setup is dialed in


Some better FYI video's on trailer sway. First two addresses tongue weighting and where the weight should be o the trailer

https://www.youtube.com/watch?v=i2fkOVHAC8Q This one has an adjustable trailer axle location. What they didnot show is, that if the trailer axle was moved rearwards, it would tow better, but would have a heavier tongue weight. Why higher class TV's has higher rear axle GVWR's

https://www.youtube.com/watch?v=w9Dgxe584Ss

https://www.youtube.com/watch?v=GWJ4Iy6ek24 this one talkes about WD hitches



Good luck and post back on how it works out for you

Edit...many will say weight ratings are not that important, but I'm not one of them. Sure you can go over, to even way over, but I'll not ever recommend that.

Just note that all things designed/engineered is for the worst day out there when Mr Murphy crosses your path when you'll need every ounce of safety factor the designers/OEM dialed in...and either you have it spot on or not.

Finally, on this is the drivers experience and knowledge factor. What will you do if/when you encounter that situation? Educate yourself well...

First off sway must be defined. Many call the suck and pull from trucks passing sway. I don't think so.
Many call being blown around by the wind sway. once again no, although sway can be precipitated by either of these

Real sway can be compared to "death wobble". A combination of events and physical characteristics combine into an unstable condition.
Swayis most often induced by being tail heavy and the vagrancies introduced by being unbalanced
Personally just from the information here ,I would say 33' is too long.

Aaaand we’re off on another rvnet weight police adventure!!
OP, no one can tell you how stable a theoretical 28-33” trailer will be. And peoples definitions of “sway” vary wildly.
Some think if you can feel the trailer back there it’s swaying and the other end of the spectrum is full on out of control trailer sway.
Sorry can’t give you a solid answer, but there will be plenty more “advice” forthcoming on this thread I predict.