Auto suspension levelers and towing

[woggy718]

I posted this on the towing forum and didn’t get much response so I figured I’d post it here to get more feedback.

Looking for some advice. My tow vehicle is 2018 GMC Yukon Denali XL and has automatic levelers in the rear suspension.

I am heading to pick up our new trailer this weekend (our family’s first camper) and my question is how will the automatic levelers affect using a WD hitch?

I did call the GMC dealer and they said it wouldn’t be an issue at all and would actually be to my advantage a little bit. My concern is the airbags inflating to get me level instead of the WD hitch doing what it’s supposed to do, causing extra stain on the system.

So what should I do? Should I turn the vehicle off, hitch up, set the bars. And then start the vehicle?

Or am I just way overthinking this?

[ttavasc]

I have the four corner active air suspension on my RAM 1500 and had similar questions when we got our trailer a few years ago. What you want to do is temporarily disable the suspension before setting up or adjusting the hitch. On the RAM there is a setting called "Tire Jack" mode that completely disables the suspension.

For the initial setup I measured height from the ground to the top of the coupler with the trailer level. Then I adjusted the ball height on the hitch to be about 1-1.5" below that measurement. This ensures that later when the suspension is re-engaged it won't lift the tongue above level which can cause instability. A little nose down isn't a problem and is what I prefer for my setup.

Once the initial hitch height is set drop the tongue on the hitch and proceed to perform the weight distribution adjustments. You can measure the difference in front wheel well height before placing the tongue on the hitch and after and adjust according to your tow vehicles recommendation for front axle load restoration.

Once the weight distribution adjustments have been made you can then re-engage the suspension and it will level and remove any remaining sag in the rear. That won't really have any effect on the weight distribution, at least not that I've seen. I scaled mine with weight distribution engaged and with the suspension off and on and didn't see a difference in the axle weights.

Going forward I would continue to disable the suspension any time you are going to hitch up the trailer as well as unhook it. It can be a challenge to lift the tongue off the hitch when the suspension keeps raising the rear as the weight comes off it.

[woggy718]

I don’t think I can turn it off. I’ve looked through the manuals, and the options menu. I don’t think that’s even an option. Turning off my vehicle is my only option I think.

[RogerR]

I have a Jeep with full air suspension (Grand Cherokee Overland) and it has an Entry setting. This lowers it down to the lowest it can get. A boon to those of us with replacement knees.

I started at this point in mine as about 1.5 inches lower than normal ride height and adjusted my ball as appropriate.

Air levelers do not effect WDH by moving weight off the rear axel and onto the front. All they try to do is level the vehicle. On mine you can feel that floating feeling in the steering if I do attach my WDH and set it correctly.

With my Andersen it is easy to set to get it right. Not sure how to do it with bars. But when you do have it set where it seems right the quickest way is do a trial run in safe areas or to take it and weight the axles which takes more time but is more precise.

[ttavasc]

Originally Posted by woggy718

I don’t think I can turn it off. I’ve looked through the manuals, and the options menu. I don’t think that’s even an option. Turning off my vehicle is my only option I think.

If turning off the vehicle is the only option to disable the suspension then I'd do that before doing any setup or adjustment for the hitch. On my RAM the suspension is active even when the vehicle is turned off. On occasion as I walk by it in the driveway shortly after parking I will hear the compressor running as it makes a slight adjustment. I guess you'll know as soon as you drop the loaded tongue on the hitch if it's really off when the vehicle is turned off - if not I'd expect it to raise the hitch up as soon as the weight is there.