Sway Control - Who Saved the Day?

4bamayoungs wrote:
After much research I outfitted the crew with a 2012 Suburban with full towing package, a Tekonsha P2 brake controller, and a 32' Coachmen Freedom Express.

we set out with full water tanks a little heavier than normal.

About 20 miles down the road, I had to move left in the lane to avoid a recap in the road and it started a sway that despite all my concentration kept amplifying and within a few seconds it became obvious that I was in trouble.

The sway got worse and worse until it was more like a whiplash effect and I was already starting to decide which side of the interstate I wanted to go off.

Suddenly there was a loud groaning noise and the trailer snatched the Suburban back straight. The noise went away and I was driving serenely along my merry way again.

After the shakes went away and I finished my thanksgiving prayers, I evaluated all the sensations I felt and it was pretty obvious that the trailer brakes had activated to stop the sway. After some limited research however, I have not been able to figure out if this was a safety feature of the brake controller or the Suburban. Can anyone shed a little light for me?

Hi 4bamayoungs,

First off, glad you made it out of this adventure in good shape. That was a very close call. Someone was looking out for you and your family that day. Remember to thank them.

I will see if I can help shed some light on your situation. I used to tow with several GM vehicles before the F350 in my sig came into the equation with our current 32 ft TT. Specifically I had a 2003 K2500 Suburban and a 32 foot TT. Before that we had the same Suburban and a 26 ft TT and before that we had the same 26ft TT with a 2002 Tahoe. I have had several learning experiences from every one of them dealing with WD on the truck and towing stability of the combined rig. And helping others with their setups. I also grew up on a farm like you operting about anything with tracks or wheels. As you know, someone from that background knows something about machinery. And so do you. Just towing a TT down the road at speed can be "different" but still all that knowledge helps.

I know you are on a quest to sort out what snapped you back into control, and after some investigation I can speculate on that too, but we need more information first. And I recommend you should have a bigger concern. What factors set the rig off in the first place? And how can I prevent it again in the future? I suspect at this point it is not just one, but several factors aligned just right and the rig become unstable. A review into all the factors needs to be reviewed to help how to correct this for the future. And to learn what each factor is to be aware of them.

This will be a learning post for sure. I can tell by your responses so far, you can handle yourself well and you are truly trying to learn. And so are we. Every now and then we have someone come forward that had a very bad event and we too as an RV'ing community can learn from you.

If you want to dig deeper into this, please tell us these answers as a start. Basically we are doing close to a full towing setup review.

1. The truck,

Is it 4 x 4 or 2 x 4 wheel drive?
Does it have any type of air suspension on the rear axle? Auto ride etc?
What engine size and rear axle ratio?
Confirm, your truck has independent rear coil springs?
What size tires and brand are on the truck?
What max psi cold pressure is stamped on the sidewall of the tire on the truck?
Are the tires the original size from GM?
What air pressure was in the front and rear tires when the event happen?
What does the door sticker state for air pressure front and rear?
What are the axle ratings off the door sticker front and rear? GAWR-RR, GAWR-FRT
What is the GVWR.
Does the sticker give a cargo capacity?

2. The WD hitch

What brand/type?
What size WD bars?
I'm assuming you where using qty 1, friction bar for anti sway control, please confirm.
Did you setup the WD hitch last or the dealer?
Have you ever done fender height measurements unhitched, truck loaded and then when the WD bars are on and tensioned up?
Is the camper level, nose down or nose high when being towed?
Any chance of a few pics of the WD hitch setup?
How do you route the emergency breakaway cable to attach to the truck?

3. The camper,

What model and year is the 32 foot Freedom Express?
What air pressure was in the tires for this trip?
What size and load range tires are on the trailer?
Can you measure from the tow ball to the center of the front axle distance?
Can you measure from the front axle center to the rear axle center?
Can you measure from the center of the rear axle to the center of the fresh water tank?
How many gallons is your fresh tank?

4. Weights, by any chance do you have scaled weights of the truck and camper? If so, what are they?

If no weights,
How many pounds of people are in the front seat of the Burb?
How many pounds of people are in the second row seat of the Burb?
How many pounds of people are in the 3rd row seat of the Burb?
How many pounds of cargo was behind the 3rd row seat?

5. The towing event day.

What speed were you traveling at when the event started?
Was the rig stable until you started that swerve to avoid the recap?
Was there any wind blowing at the time that you noticed?
Did you swerve off the pavement any and then come back on? Meaning your left the pavement, the shoulder was lower and you came back on.
Go through your mind and try and recall every step you did in what order at the start of the first swerve until the end when it straightened out. This will be very helpful. Please include what you did with the truck brakes, the brake controller, steering corrections and vehicle speed throughout the event.

I know this seems like a lot to go through, I'm hoping you want to understand it and learn from it. Every question has a reason on how this all fits together. And glad to explain them all, but this info gives us more to go on. Try your best to answer accurately.

Hope this helps

John