I had a interesting thing happen while I was towing my 24' enclosed trailer (with a Yukon XL Denali) coming home from Summit Point yesterday. It was raining and I was driving the back roads toward route 81. I rounded a curve at about 40 mph and the trailer literally pushed the back of my Denali straight out of the corner.

It cause a bigtime oversteer moment, but I was able to correct for it and continue on. It has me a little perplexed because I am running with plenty of tongue weight, load leveling bars and the new dual cam sway control. I always thought that the trailer would start to slide before my car would. Could thins new type of sway control have caused it? Anyone else have something similar happen?

 

I'm running the Reese Dual Cam/Anti sway system and pull a 24' enclosed with my 3/4 ton, haven't had anything like that occur in rain or otherwise and I drive the back roads of CT like I have nothing behind me.. wish I could be more help Larry.

 

That is tha exact setup that I have, and it has run flawlessly till this incedent. It doesn't have me concerned because I knew that I went in a little hot, but I expected the trailer to slip a little, not to push the back of my truck out.

 

I wonder if the electric trailer brake if applicable did not work as you applied the brakes prior to the turn causing the trailer to not slow down with the truck then the trailer unweighted and pushed the truck by means of inertia?

 

I was thinking the same thing but he didn't mention a brake application. Were you on the brake at the time Larry?

 

No, I don't think so, but I was definitely off the gas. I could see where not having enough trailer brakes in that situation could cause it. Wish I had the video on.

 

Load equalizer bars 'load' the front suspension of the tow vehicle by taking load off the back suspension. You get better front brake action in crappy conditions, but there is no free-lunch...too much 'pre-load' in those equalizer bars can do this.

Several things to consider:
Weight & size of trailer ?
Weight & wheelbase of tow vehicle ?
Available traction ?

I hated towing in the enclosed 24' in the wet until I got the crew-dually. Even though the previous tow vehicles were diesel trucks (cargo vans etc, that were 6K+), they were a real handful in the wet. In poor conditions in the past, I have chosen to just 'park it' and wait for weather to improve (wait for salt trucks & plows, wait until the monsoon stopped...etc.).

 

A big trailer will push the butt-end of the truck around - see it all the time in the day job. Just unusual that it pushed it that hard. PS - that's even without all the extra tow gear you have there, just using a regular ball hitch no extras.

My prescription? Upgrade to a new Yukon (07+) with stability control... though I don't remember if they have trailer sway control (maybe?)...

 

Larry, possibly drop a link on the equalizer bars next time?

 

Gary, they are already set fairly softly, as the air suspension still has to raise the back a few inches to get it level. I am not overly concerned, but raised the question because I was wondering if others might have experienced the same thing.

 

I've had that happen a few times when I was pulling about 12,000 pounds of dinosaur bones with a short box crew cab F-350 load distributing hitch etc. etc.. It would happen in similar situations where weight of the truck would transfer forward, either by braking or by just lifting. I generally would get the truck slowed down before the curves and be at my lowest speed at the beginning of the turn. If I had to slow down a bit I'd often just use the trailer brakes.

It was definitely unnerving the first time I felt it and with 20,000 pounds of truck and trailer doing what it wanted and not necessarily what I wanted very quickly raised my heart rate.

 

It is not unusual entering a corner where you lift. The trailer is being slowed only through the hitch. It is worse if the turn is somewhat downhill as the trailer is pushing even harder. Apply a little trailer brake via the controller and I bet it would do fine.

 

Larry does the Denali have QuadraSteer?

 

No, that was only available in the pickups, not in the Yukon line. I'll bet that option can make towing interesting at times.

 

Probably a combination of inertial inputs to the trailer via the hitch, road conditions, trailing throttle, those sway bars, and the air suspension. I am not a big fan of any air suspension, especially GM's.

You should have manned up & gotten the Yukon XL 3/4 ton instead of he sissy Lord of the Blings DUH-nali...