Sway Control Info

I just got my travel trailer, so only have a few hundred miles towing it. But it is about 4k lbs and I don't seem to need any away control. I have a 1 ton srw Cummins. I had no problems at 65-70 even around semi trucks. Every once in a while I thought I might have seen the smallest sways in rear view mirror but not enough to even feel in the truck. Add tongue weight and hammer down.

Lack of enough tongue weight is what causes sway with a TT. Put heavy things in the front of the TT and go camping. With your truck you cannot have too much tongue weight.

I agree with everyone so far. Load the TT correctly balanced.
Don't confuse sway with the push n pull of overtaking trucks (thats normal)
Look at all the enclosed 30-35 ft (5000 lb) ATV/snowmobile trailers being towed direct to the ball without a WD hitch or sway control. Year after year and many thousands of miles.

We just returned back home from a (steady 20mph with 30mph wind-gusts) 500 mile tow using a 3000 lb loaded enclosed v-nose trailer direct to the ball using a 1500 truck with the truck bed also loaded up. Because the unloaded truck sits rear end high with a max tow package, the combo towed level once i hitched up with a 1.5" squat. No issues at 65-70mph. I had to do a minor headlight adjustment. It towed flawlessly. My DW towed it for 150 miles and she loved it.


MY TT:
The transporter who towed my TT half way across the country from the mfg to the dealership towed it direct to the ball using a dual wheel 350 truck. NO WD hitch and no SC.

Im towing a Jayco 23 RB (27 ft) @6000# wet with approx 800# TW (its 100# more when i bring the bikes on my tongue mounted bike rack, see my profile pic) with a max tow pack silverado 1500 with a Pro series Reese and friction sway bar.
I've tried the system both ways to see how it tows. So far (about 5k miles) i have not noticed any difference with or without the sway bar.

I also tried this same 6000# Jayco using my beefed up 2500HD and it it towed perfectly direct to the ball as well as using the WD hitch which i didn't feel any difference in the tow. Wheel well measurements were also in check however, it did squat a tiny bit in the rear but not enough to feel any towing difference or affect steering.
I did have 'Tork-lift adjustable Stable-loads' on my helper springs which engages the helper spring earlier than normal (without a load).

Friction sway control is cheap insurance. Unexpected stuff can happen. There is no downside AFAIK.

I have a friction sway control bar on my hitch, but it is not critical.

If you can find a basic weight distribution hitch with friction sway control, you will be fine (even overdoing it) and if you end up towing with something else you will be covered.

Since 2013 I've been towing our current Coachmen Freedom Express 192RBS with a 1/2 ton Chevy Avalanche, trailer measures 22' 6" coupler to bumper and typically averages ~ 4600 lbs loaded & ready to camp. I do use a trunnion bar Reese WD system as the Av's rear coil suspension otherwise sags excessively with 600 lbs of gross tongue weight bearing down on the hitch ball but I don't use any friction sway bar as in tens of thousands of miles of towing I've found it unnecessary. With your TV being a 3500 with stiff rear leaf suspension and having a much greater wheelbase than my Av's 130" I'd find it hard to imagine you'd need either WD or sway control towing such a small trailer. :)

If a trailer is properly loaded it won't sway. Having said that, I still have a sway control on mine, just a friction sway bar ($100.00±). It's just a belt and suspenders type thing for me. I usually use it but have forgotten a number of times and saw no real difference.