Sway Control

[Frankf]

Originally Posted by Katana07

After much research and eliminating several suggestions, I concluded that the issues can only lie within a handlful of problems. Light tongue weight, axle misalignment or wheels out of balance. I hooked up to the TT yesterday and towed it to a tire shop. They removed all wheels and the technician said "these wheels are obscenely out of balance". Two of the 4 wheels took a little over 7 oz. of weights to balance them. The other two wheels were somewhat normal with 2-4 oz. After contacting the dealership, I was told that Winnebago never balances their trailer tires and this is not a warranty issue nor a factory delivery concern. However crazy that seems to me, it only cost me $64.00 to have all 4 removed, balanced and re-installed. The tire shop also stated that the unbalanced tires will and can cause instability, but more concerning was the fact that the trailer has tandem axles running aggressive tread "LT" tires which stand for light truck. The tire shop said that the light truck tires were never designed to be on a trailer and the sidewalls have less strength further promoting sway. I can see that this is heavily debated on the forums and other places on the internet. I'm not here to argue that, but simply repeating what the tire shop told me. They suggested that in order to achieve higher stability, I would ultimately need to switch to high quality ST trailer tires. I am not planning on doing that as the Trail Guide All Terrain factory tires seem to have reasonable quality from my research. I might switch whenever these are near the end of their life or after several years.
I have a trip in a few weeks where I will test the stability again. If it's still acting up, I plan to measure the axles for potential misalignment. If that checks good, I'm planning on taking the trailer to a weigh station and getting some numbers put together. I need to do that anyways. If all of those numbers check good and the trailer is balanced well, my issue might truly be related to this tire situation.

Interesting. I'm waiting on delivery of a 2108DS. According to the brochure, the tires will be ST235/75R15. Guess I'll just have to wait and see. Also, I find it hard to believe that Winnebago would put unbalanced wheels/tires on a new travel trailer.

[backtrack15]

A couple things:

(1) Yes, the 2021B trailers have different tires. They are now Westlake ST tires. A few of the very early builds got the previous tires.

(2) The 2021B trailers have lower cargo carrying capacity (2000 lbs lower) since they revised the GVWR to 5000. The 1708, 180X, and 210X trailers all have 2500# axles now.

(3) I'd expect the F-350 to drop about an inch or so with an 800 lb tongue load. My old fifth-wheel dropped my F-350's rear by about 2.125 inches with 2000 lbs of pin load.

[Goodspike]

The material available on the Internet about LT tires on tandem axle trailers is concerning, but I don't know if it's right. I can't imagine it would make much difference when going straight though--I think the issue is corners.

FWIW, this week I was loaded up a bit more than prior tows, and on the way back I had more water in the black and grey tanks than I've had with this trailer in the past (I usually dump where I camp). Just moving probably 15 may 20 gallons of water from the middle of the trailer to the back did seem to cause some moderate jerking action at times--not actual sway. Makes me wish I'd taken my tongue scale with me, but I hadn't. But I could see that having 160 extra pounds or so back in the back would make a difference.

[Katana07]

Originally Posted by Goodspike

The material available on the Internet about LT tires on tandem axle trailers is concerning, but I don't know if it's right. I can't imagine it would make much difference when going straight though--I think the issue is corners.

FWIW, this week I was loaded up a bit more than prior tows, and on the way back I had more water in the black and grey tanks than I've had with this trailer in the past (I usually dump where I camp). Just moving probably 15 may 20 gallons of water from the middle of the trailer to the back did seem to cause some moderate jerking action at times--not actual sway. Makes me wish I'd taken my tongue scale with me, but I hadn't. But I could see that having 160 extra pounds or so back in the back would make a difference.

Goodspike,

Thanks for this information/story. Your description of intermittent jerking action is very close to what I am experiencing. I plan to take my trailer out in the next week or so to go camping. I'm hoping this wheel balance situation will help, but am also anticipating it might not. I'm definitely going to have the rig weighed during this trip somewhere on some CAT scales. I would ideally like all my tanks to be empty to simulate the lightest pulling load possible. I'm anxious to see what the tongue weight is. On my model, I can always add more weight under the bed if necessary.