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Trailering: WDH adjustment with E-Active Body Control
I am about to set up our new GLE450, which has E-ABC, with our Weight Distributing Hitch.
In order to do this with the technique I use (equal depression at each corner of the tow vehicle), I need to disable the self-leveling feature of the Air suspension, and also E-ABC, while I adjust the WDH tension bars. It seems that the suspension is active for a while after shut-down, as I hear some adjustments as people exit or I remove cargo from the rear.
Does anybody know how to disable the suspension while doing this?
Is there a suspension height that the GLE450 defaults to when the 7-pin is connected, causing the vehicle to sense a trailer? (Comfort, Sport or ???)
Does it maintain that setting, or one that I have chosen, during the entire towing event? (I hope so because tongue height affects weight transfer.)
I am happy to have the 450 level itself, but only after I have adjusted the weight transfer.
Good question,mikapen. I will be waiting for the answer(s) on this. You may need to level it with the engine off for a bit and hope it is "good enough" for when the E-ABC is working. Does the E-ABC leveling function redistribute any weight all by itself? I guess a trip to the scales with and without the WD hitch to see the differences might give some insight. Since a WD hitch does more that just level, I would still say using one has major benefits. How much weight are you towing? Still waiting for our GLE450 with E-ABC. It has been "built but not shipped" for 3 1/2 weeks now.
....Does the E-ABC leveling function redistribute any weight all by itself? I guess a trip to the scales with and without the WD hitch to see the differences might give some insight.....
A self-leveling air suspension does nothing to redistribute weight to the steering axle - a WDH is needed for that.
And since I push the M-B's GVWR limits with my 6,000# trailer, 720# tongue weight, I would overload the rear axle without a WDH. (Which also distributes part of the tongue weight back to the trailer axles.) Not to mention the loss of steering control without good transfer forward.
What's necessary to set up the WDH is that the suspension not do anything to change the heights, since I measure how much each corner of the TV goes down with various tensions on the WDH bars. I don't use scales for that adjustment, but I will use scales to verify that I'm not over GAWR for either of the axles.
I have towed that trailer a lot with my previous ML350 Bluetec's and it's an impressive combination.
My Salesman is researching by reaching out to M-B, but no word yet.
Hoping for some good input from the Forum.
A self-leveling air suspension does nothing to redistribute weight to the steering axle - a WDH is needed for that.
And since I push the M-B's GVWR limits with my 6,000# trailer, 720# tongue weight, I would overload the rear axle without a WDH. (Which also distributes part of the tongue weight back to the trailer axles.) Not to mention the loss of steering control without good transfer forward.
What's necessary to set up the WDH is that the suspension not do anything to change the heights, since I measure how much each corner of the TV goes down with various tensions on the WDH bars. I don't use scales for that adjustment, but I will use scales to verify that I'm not over GAWR for either of the axles.
I have towed that trailer a lot with my previous ML350 Bluetec's and it's an impressive combination.
My Salesman is researching by reaching out to M-B, but no word yet.
Hoping for some good input from the Forum.
What is your objection to letting the vehicle level itself? Set the tongue on the ball, tension the spring bars, plug in the 7-pin, start the vehicle and wait while it does its thing. Do you object to that procedure?
As an academic experiment, you could do the above procedure without plugging in the 7-pin to see if there is a difference. The vehicle wouldn't know if a trailer was connected, or if it was loaded with two fat ladies and a load of potatoes in the back.
I am about to set up our new GLE450, which has E-ABC, with our Weight Distributing Hitch.
In order to do this with the technique I use (equal depression at each corner of the tow vehicle), I need to disable the self-leveling feature of the Air suspension, and also E-ABC, while I adjust the WDH tension bars. It seems that the suspension is active for a while after shut-down, as I hear some adjustments as people exit or I remove cargo from the rear.
Does anybody know how to disable the suspension while doing this?
Is there a suspension height that the GLE450 defaults to when the 7-pin is connected, causing the vehicle to sense a trailer? (Comfort, Sport or ???)
Does it maintain that setting, or one that I have chosen, during the entire towing event? (I hope so because tongue height affects weight transfer.)
I am happy to have the 450 level itself, but only after I have adjusted the weight transfer.
Remove the power to E-ABC/air suspension— find the fuse and pull it.
What is your objection to letting the vehicle level itself?
Without a WD hitch, the trailer's tongue weight pushes the back of the truck down which makes the truck's front axle become "light" (takes weight off the axle). This lessens the truck's steering and braking capabilities.The problem is that simply leveling the vehicle does not distribute the weight. The purpose of the WD hitch is to spread the trailer's tongue weight more evenly between the axles of the truck and trailer, most importantly to the front axle of the truck. My concern would be that the GLE's leveling system might exacerbate the problem by lightening the front axle even more than if you had the sag. (A minor change at best.)
When properly setup as mikapen explained, some of the trailer's tongue weight is shifted to the truck's front axle, restoring the steering and braking capabilities. The GLE's leveling system would make the truck and trailer level, no matter how the tension on the WD hitch is set. This would leave you unable to set the proper WD hitch tension and determine when the weight is distributed properly. The hitch tension determines how the weight is spread through out the truck/trailer combination.
Remove the power to E-ABC/air suspension— find the fuse and pull it.
That's a good thought. I think that's the approach on Lincolns, although other makes like Jeep Grand Cherokee have a "tire change mode."
Now to find the fuse, and I'll ask my Service Department if that would cause something to go haywire.
Without a WD hitch, the trailer's tongue weight pushes the back of the truck down which makes the truck's front axle become "light" (takes weight off the axle). This lessens the truck's steering and braking capabilities.The problem is that simply leveling the vehicle does not distribute the weight. The purpose of the WD hitch is to spread the trailer's tongue weight more evenly between the axles of the truck and trailer, most importantly to the front axle of the truck. My concern would be that the GLE's leveling system might exacerbate the problem by lightening the front axle even more than if you had the sag. (A minor change at best.)
When properly setup as mikapen explained, some of the trailer's tongue weight is shifted to the truck's front axle, restoring the steering and braking capabilities. The GLE's leveling system would make the truck and trailer level, no matter how the tension on the WD hitch is set. This would leave you unable to set the proper WD hitch tension and determine when the weight is distributed properly. The hitch tension determines how the weight is spread through out the truck/trailer combination.
@Brer Rabbit Did you see in the post you partially quoted, the step about tensioning the (WD) spring bars?
Let the vehicle level itself with a WD hitch. The vehicle doesn’t know if a carload of circus clowns are inside, or if a trailer with a WD hitch is connected.
@Brer Rabbit Did you see in the post you partially quoted, the step about tensioning the (WD) spring bars?
Let the vehicle level itself with a WD hitch. The vehicle doesn’t know if a carload of circus clowns are inside, or if a trailer with a WD hitch is connected.
Sorry, I thought you meant letting the vehicle level just using the E-ABC. I must have still been asleep.
@Brer Rabbit Did you see in the post you partially quoted, the step about tensioning the (WD) spring bars?
Let the vehicle level itself with a WD hitch. The vehicle doesn’t know if a carload of circus clowns are inside, or if a trailer with a WD hitch is connected.
And that's the problem. There is a big towing difference if the load of clowns is within the car's wheelbase, or loaded on the hitch, behind the bumper.
A load behind the bumper unloads the front steering axle and contributes to sway. And probably overloads the rear axle. A load of clowns inside the car loads both axles.
If you let the car level itself before you set up the WDH, you won't be able to judge the amount of tension needed to restore weight to the front axle. The self-leveling needs to be disabled in order to do a setup.
So the sequence needs to be: 1. Self-leveling off. 2. Adjust WDH for proper weight transfer. 3. Self-leveling back on.
The car can now do what it wants, now that you have "un-overloaded" the overloaded rear axle and "re-loaded" the steering axle.
What is your objection to letting the vehicle level itself? Set the tongue on the ball, tension the spring bars, plug in the 7-pin, start the vehicle and wait while it does its thing. Do you object to that procedure?
As an academic experiment, you could do the above procedure without plugging in the 7-pin to see if there is a difference. The vehicle wouldn't know if a trailer was connected, or if it was loaded with two fat ladies and a load of potatoes in the back.
I have no objection to having the car do its leveling thing AFTER the spring bars are adjusted, and the weight is distributed. The operative thing here is "weight distributed," not "level." If the weight is distributed properly, the car will be level without "self-leveling" intervention. Until you throw your sack of potatoes in the back, at which time it would re-level.
My original question was how to disable the self-leveling, so you can accurately set the WDH spring tension. It seems that the leveling is active with the ignition off, but maybe after a half hour or two it becomes inactive.
An earlier post about removing the fuse may be the answer - I'll investigate and report back.
And your thought experiment about letting the GLE level with and without the 7 pin connected would be interesting to see, but I think all it would tell would be if the GLE chooses a different ride height with a trailer, than without.
Just to make sure we are all paddling down the same stream:
The vehicle needs to be loaded with its normal trip stuff (if that includes clowns, that's on you). The trailer needs to be loaded with its normal stuff: water, food, camping chairs....... The trailer is hitched to the vehicle. ALL other leveling aids (E-ABC, inflatable airbags, pneumatic struts........) need to be off/disabled/non-functioning. The vehicle is then leveled by (and only by) adjusting the torsion on the WDH via the procedure describe by Mikapen in the first post (that is what I do anyway). This will properly shift the weight to the front axle for the reasons stated in my prior post. The E-ABC, airbags, struts, etc do NOT shift that needed weight back to the front axle. They simply lift the rear axle to make the vehicle lever, the weight is still on the back axle and the front axle is still light.
Hope that clears it up. The car would (or could) in fact know if it was a load of clowns or an improperly adjusted WDH by the difference in the weight on the front and rear axles. A bunch of clowns inside would more evenly distribute the weight. An improperly adjusted WDH would be back axle heavy.
@mikapen Why do you need to deactivate E-ABC, in other words, the levelling system? You are harping on a point that no one is debating you on.
Fire the car up, hitch up on a level surface, tension the WD bars, plug in the 7-pin, load the trailer with camping chairs and pancake mix, and load the vehicle with fat ladies and potatoes.
Then let Gottlieb's creation do its thing. If you are within GAWR, GVW and GCW you need not worry.
Et voila, Bob's your uncle. Unless of course the fat ladies get out of the vehicle and the whole process starts from the beginning.
@mikapen Why do you need to deactivate E-ABC, in other words, the levelling system?
Maybe there is a misunderstanding of how the WD hitch works. There are several amounts of tension what can be applied with the WD hitch. The correct amount of tension takes the hitched vehicle/trailer from a dipped condition:
to a level condition:
This leveling is accomplished by adjusting the hitch tension until the level condition is achieved. If something else (E-ABC) is leveling the vehicle, there is no indication as to when you have reached the correct torsion. If the E-ABC is active, any amount of torsion will lever the vehicle and you do not know when the WD did its job. It is NOT the leveling of the vehicle that is the primary goal. The primary goal is to properly distribute the weight between the vehicle's front and rear axles. The vehicle leveling is the indication that the weight is correctly distributed.
Maybe there is a misunderstanding of how the WD hitch works. There are several amounts of tension what can be applied with the WD hitch. The correct amount of tension takes the hitched vehicle/trailer from a dipped condition:
to a level condition:
This leveling is accomplished by adjusting the hitch tension until the level condition is achieved. If something else (E-ABC) is leveling the vehicle, there is no indication as to when you have reached the correct torsion. If the E-ABC is active, any amount of torsion will lever the vehicle and you do not know when the WD did its job. It is NOT the leveling of the vehicle that is the primary goal. The primary goal is to properly distribute the weight between the vehicle's front and rear axles. The vehicle leveling is the indication that the weight is correctly distributed.
@Brer Rabbit Whose post are you replying to? I have towed with a WD for tens of thousand of miles over a 10 year period. My lumbar discs have the bulges to prove it, from tensioning spring bars. I am intimately familiar with WD hitches. Are you directing your post to mikapen?
There is a lot of people talking past each other, and in my view mikapen is belaboring something that doesn't need belabored.
The leveling system, also known as E-ABC, levels. The WD hitch system does just that, it distributes weight.
Hitch up and get the wheels turning. Don't forget the fat ladies and camping chairs.
Chassis, I think the impression we are getting is that you want to adjust the WD hitch with the E-ABC on. Turning the E-ABC on after adjusting the WD hitch is fine.
Chassis, I think the impression we are getting is that you want to adjust the WD hitch with the E-ABC on. Turning the E-ABC on after adjusting the WD hitch is fine.
Yes, as has been written in multiple posts. Do you object to this?
@mikapen Why do you need to deactivate E-ABC, in other words, the levelling system? You are harping on a point that no one is debating you on.
Fire the car up, hitch up on a level surface, tension the WD bars, plug in the 7-pin, load the trailer with camping chairs and pancake mix, and load the vehicle with fat ladies and potatoes.
Then let Gottlieb's creation do its thing. If you are within GAWR, GVW and GCW you need not worry.
Et voila, Bob's your uncle. Unless of course the fat ladies get out of the vehicle and the whole process starts from the beginning.
Um, because if the leveling system is active, as I and @Brer Rabbit keep saying to you, it's impossible to adjust the WDH tension to get the proper weight transfer. (sigh) @chassis , I am responding directly to you: It might help if you read my original post, and were more direct in your comments. Scroll up so I don't have to re-state my question again, please. That would be post #1. Thanks.
OK I'll state my question again. Does anybody know how to disable a 2020 GLE450 leveling system? HTH
I don't know anything about towing so this may be a useless suggestion, but with e-ABC you have the off-road assistant feature, and one of the options there is to set the suspension for each of the 4 wheels individually. So, if you're on a flat surface and go into that mode, then make sure the 4 wheels are at the same suspension level, wouldn't everything stay put while you set up the WD hitch? I assume it wouldn't do any leveling since you're manually in control of each wheel. Then when you're done with the weight distribution you can get out of the off-road assistant mode and back into comfort mode.
If this isn't one of the world's stupidest ideas, I guess one of the downsides is you need to be in Drive to activate the off-road asistant, which may not be desirable while hooking up your trailer.
chassis, how do you INITIALLY set the tension of the WD hitch? I think that is the first and primary question that is being asked.
Originally Posted by maalox
I don't know anything about towing so this may be a useless suggestion, but with e-ABC you have the off-road assistant feature, and one of the options there is to set the suspension for each of the 4 wheels individually. So, if you're on a flat surface and go into that mode, then make sure the 4 wheels are at the same suspension level, wouldn't everything stay put while you set up the WD hitch? I assume it wouldn't do any leveling since you're manually in control of each wheel. Then when you're done with the weight distribution you can get out of the off-road assistant mode and back into comfort mode.
If this isn't one of the world's stupidest ideas, I guess one of the downsides is you need to be in Drive to activate the off-road asistant, which may not be desirable while hooking up your trailer.
hey maalox, that is another approach but again I think there is a problem in that you do not want "everything to stay put". As you increase the tension in the WD hitch, the front of the vehicle begins to lower. You continue to increase the tension until the front of the vehicle is at the same level it was when no trailer is hitched. That is how you know the weight is properly distributed. If the E-ABC is messing with the front of the truck moving due to the weight being distributed, you will get a false setting.
Looking back at this thread, I think I see why @chassis was confused. In my OP, I said "I am about to set up our new GLE450, which has E-ABC, with our Weight Distributing Hitch." Apparently I wasn't clear that I the reason I wanted to "disable the suspension while doing this," was to make the initial adjustments. Which requires a self-leveling suspension to be inactive so you can actually see the results of your adjustments.
Once you have your WDH dialed in, you can certainly "Fire the car up, hitch up on a level surface, tension the WD bars, plug in the 7-pin, load the trailer with camping chairs and pancake mix, and load the vehicle with fat ladies and potatoes," as @chassis wants to do.
There are several things to adjust when setting up a WDH for the first time with a new rig. Ball height, hitch head angle, spring bar (or other mechanism) tension, tailgate clearance. It's important to spend time doing this and getting it right.
In my case, I am just moving my WDH from my (second) ML350 Bluetec to the new GLE450, but it's still a clean sheet because almost everything is different. It's a safety thing.
Looking back at this thread, I think I see why @chassis was confused. In my OP, I said "I am about to set up our new GLE450, which has E-ABC, with our Weight Distributing Hitch." Apparently I wasn't clear that I the reason I wanted to "disable the suspension while doing this," was to make the initial adjustments. Which requires a self-leveling suspension to be inactive so you can actually see the results of your adjustments.
Once you have your WDH dialed in, you can certainly "Fire the car up, hitch up on a level surface, tension the WD bars, plug in the 7-pin, load the trailer with camping chairs and pancake mix, and load the vehicle with fat ladies and potatoes," as @chassis wants to do.
There are several things to adjust when setting up a WDH for the first time with a new rig. Ball height, hitch head angle, spring bar (or other mechanism) tension, tailgate clearance. It's important to spend time doing this and getting it right.
In my case, I am just moving my WDH from my (second) ML350 Bluetec to the new GLE450, but it's still a clean sheet because almost everything is different. It's a safety thing.
Bottomline, he needs the E-ABC off when he first hitches up the trailer to initially sets up his weight distribution hitch on his GLE. To do it correctly, he needs to ensure the weight of the trailer tongue doesn't cause more than a 1 inch difference between the height of the front and rear of his GLE (compared to when it's not hitched his trailer) -- less than a 1 inch difference means he has the weight distribution hitch set up correctly. If he has the E-ABC on when he initially sets up his weight distribution hitch, it will raise the rear of his GLE and he'll have no idea how much tongue weight the rear axles are supporting.
A properly set up weight distribution hitch means the rear axle of his GLE will be supporting less tongue weight because some of the weight of the trailer tongue is being distributed back to the rear axle of this trailer and to the front of the GLE via the tension in the hitch spring bars. The hitch spring bars act like the handles of a wheelbarrow to lift the back of the GLE and push the front of the GLE down. Once he sets it up correctly, he never has to do it again.
Got it. It wasn't clear to me in the original post that @mikapen was setting up the WD head from scratch.
Why is is mandatory that E-ABC be deactivated while setting up the hitch? The procedure is trial and error with an old fashioned suspension, as it is with E-ABC. It seems like extra steps, time and effort to deactivate E-ABC after each adjustment of the WD head.
Again, the vehicle doesn't know if a dozen circus clowns are in it, or a travel trailer is hitched.
Got it. It wasn't clear to me in the original post that @mikapen was setting up the WD head from scratch.
Why is is mandatory that E-ABC be deactivated while setting up the hitch? The procedure is trial and error with an old fashioned suspension, as it is with E-ABC. It seems like extra steps, time and effort to deactivate E-ABC after each adjustment of the WD head.
Again, the vehicle doesn't know if a dozen circus clowns are in it, or a travel trailer is hitched.
I think what the OP wants to avoid, is to have the E-ABC system adjusting the suspension level while trying to trying to distribute the weight.
For example, let say the normal suspension is sitting at level 5 (using 0 to 10 as a scale, with 0 means its all the way down, 10 means all the way up). At this time, the front and back are both sitting at level 5, with 60% of the weight in front, and 40 in back. (again not real number, just an example).
Now let say a trailer is attached. Now the height is at level 7 on front, level 3 on rear, with 40% weight on front, and 60% on back.
With a normal suspension, we will try to setup the WD so that it is close to the original, so level 5 on both front and rear (which also indicate 60% - 40% front rear ratio).
But with E-ABC, the suspension auto leveling system might come into play. In this case (before WD adjustment), the front suspension might lower, and raise the rear. Both will sit at level 5, but the weight didn't change, (still 40% front, 60% rear). The rear suspension just work "harder" to make it look level.
To OP, here is what the manual said:
So the auto level system should be off if you follow the condition above in the warning section.
I think what the OP wants to avoid, is to have the E-ABC system adjusting the suspension level while trying to trying to distribute the weight.
For example, let say the normal suspension is sitting at level 5 (using 0 to 10 as a scale, with 0 means its all the way down, 10 means all the way up). At this time, the front and back are both sitting at level 5, with 60% of the weight in front, and 40 in back. (again not real number, just an example).
Now let say a trailer is attached. Now the height is at level 7 on front, level 3 on rear, with 40% weight on front, and 60% on back.
With a normal suspension, we will try to setup the WD so that it is close to the original, so level 5 on both front and rear (which also indicate 60% - 40% front rear ratio).
But with E-ABC, the suspension auto leveling system might come into play. In this case (before WD adjustment), the front suspension might lower, and raise the rear. Both will sit at level 5, but the weight didn't change, (still 40% front, 60% rear). The rear suspension just work "harder" to make it look level.
To OP, here is what the manual said: <snip>
So the auto level system should be off if you follow the condition above in the warning section.
Exactly. That's why I want to disable it, and why I asked how to do that.
The manual says that the suspension will "return to previously selected position" after it may raise then lower, which kind of implies that it's standing watch. Just what I am wanting to avoid. The system probably goes into "off" mode after a while, otherwise it would drain the battery over time. I wonder how long that is.
I'll spend an afternoon setting up things, which includes loading the trailer and then doing the adjustments. And unloading it later.
But, as has been said before, It'll be the same from there on out, so no need to repeat the setup unless something major changes.
Just hitch up and go.
(One exception to this is if you have a brand new hitch. Then it's a good idea to do another setup after a thousand miles, after everything has taken a set.)
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