Why Should Suspension Auto Level be Done Before Setting Up Weight Distribution
Published 09/18/2017 >
Question:
thank you for your answer...i will follow it...here is what i found in my owner manual (ford expedition 2012) so were right! FYI Weight-distributing Hitch – Vehicles with Air Suspension WARNING: Do not adjust a weight-distributing hitch to any position where the rear bumper of the vehicle is higher than it was before attaching the trailer. Doing so will defeat the function of the weight-distributing hitch, which may cause unpredictable handling, and could result in serious personal injury. When hooking-up a trailer using a weight-distributing hitch, always use the following procedure: 1. If your vehicle is equipped with the Easy Entry/Kneel feature, turn it off using the information display. 2. Park your vehicle, without trailer and with the ignition on, on a level surface with all doors closed for a few minutes to make sure that the air suspension has settled. 3. Measure the height of the top of your vehicle’s front wheel opening on the fender. This is H1. 4. Attach the trailer to your vehicle. Do not install the weight-distributing bars at this time. 5. With the ignition on and all doors closed, let your vehicle (with trailer) sit for a few minutes to let the air suspension re-settle. 6. With the trailer connected, but without weight-distributing bars connected, measure the height of the top of your vehicle’s front wheel opening on the fender a second time. This is H2. 7. Install and adjust the tension in the weight distributing bars so that the height of the front fender is approximately halfway between H1 and H2. Towing 259 2013 Expedition (exd) Owners Guide gf, 2nd Printing, October 2012 USA (fus) 8. With the ignition on and all doors closed, let your vehicle (now with trailer and weight distributing bars connected) sit for a few minutes to let the air suspension re-settle. 9. Re-measure the height of the top of the front wheel opening, repeating Steps 7-9 as necessary to obtain a fender height approximately halfway between H1 and H2 after the air suspension has settled. 10. Check that the trailer is level. If it is not level, remove the trailer, adjust the ball height accordingly, and repeat Steps 4–10.
asked by: Denis L
Expert Reply:
I can see how either way would "in theory" work well, but what we've gotten from our weight distribution manufacturers is that you let it auto level first and then set the system up so that the WD's spring bar tension is accurate for how the vehicle's suspension configuration and not be too severe.
Otherwise if you do the auto-level after the WD system you may end up with the WD and the air system working against each other.

Denis L.
9/18/2017
thank you for your answer...i will follow it...here is what i found in my owner manual (ford expedition 2012) so were right! FYI Weight-distributing Hitch – Vehicles with Air Suspension WARNING: Do not adjust a weight-distributing hitch to any position where the rear bumper of the vehicle is higher than it was before attaching the trailer. Doing so will defeat the function of the weight-distributing hitch, which may cause unpredictable handling, and could result in serious personal injury. When hooking-up a trailer using a weight-distributing hitch, always use the following procedure: 1. If your vehicle is equipped with the Easy Entry/Kneel feature, turn it off using the information display. 2. Park your vehicle, without trailer and with the ignition on, on a level surface with all doors closed for a few minutes to make sure that the air suspension has settled. 3. Measure the height of the top of your vehicle’s front wheel opening on the fender. This is H1. 4. Attach the trailer to your vehicle. Do not install the weight-distributing bars at this time. 5. With the ignition on and all doors closed, let your vehicle (with trailer) sit for a few minutes to let the air suspension re-settle. 6. With the trailer connected, but without weight-distributing bars connected, measure the height of the top of your vehicle’s front wheel opening on the fender a second time. This is H2. 7. Install and adjust the tension in the weight distributing bars so that the height of the front fender is approximately halfway between H1 and H2. Towing 259 2013 Expedition (exd) Owners Guide gf, 2nd Printing, October 2012 USA (fus) 8. With the ignition on and all doors closed, let your vehicle (now with trailer and weight distributing bars connected) sit for a few minutes to let the air suspension re-settle. 9. Re-measure the height of the top of the front wheel opening, repeating Steps 7-9 as necessary to obtain a fender height approximately halfway between H1 and H2 after the air suspension has settled. 10. Check that the trailer is level. If it is not level, remove the trailer, adjust the ball height accordingly, and repeat Steps 4–10.