Alternate trailer height/air suspension questions

Howdy, new owner of 2016 laramie, 6.4, w/ the OEM factory air suspension. While I was loading my travel trailer (TT) for the first time, I realized there's a lot to know about this truck that I can't find enough about in the owners manual. For example, it seem the air suspen works against me. When unhooking my TT, as I cranked the TT up, off of the ball (approx 600 lbs tongue weight) the air suspension sensed the decreasing load on the rear end and actually raised the truck up. So I'm trying to raise the TT coupler off the ball and the trucks's raising the ball as I crank. True, it only raises it a couple of inches, but its self-defeating if I'm cranking the TT coupler up too. And sometimes a couple of inches means getting the TT high enuff to slip over onto the ball during hook up or being able to drive the truck out from under the ball during off loading.
Before the test loading and unloading process, I engaged the "alternate trailer height" button inside the truck. I thought it was supposed to lower the back end a few inches to facilitate hooking up. As the automatic air suspension sensed "its own thing", I think the "alternate" (lower) height feature was defeated. Or at least minimized. Do they work against each other like this normally ?
Am I supposed to "turn off" the air suspension while loading so this see-saw thing doesn't happen ? If so, how do I ? If not, any suggestions on a "smarter" or proper loading technique.

jsummers72 said:

it seem the air suspen works against me. When unhooking my TT, as I cranked the TT up, off of the ball (approx 600 lbs tongue weight) the air suspension sensed the decreasing load on the rear end and actually raised the truck up.

So I'm trying to raise the TT coupler off the ball and the trucks's raising the ball as I crank. True, it only raises it a couple of inches, but its self-defeating if I'm cranking the TT coupler up too. And sometimes a couple of inches means getting the TT high enuff to slip over onto the ball during hook up or being able to drive the truck out from under the ball during off loading.

Before the test loading and unloading process, I engaged the "alternate trailer height" button inside the truck. I thought it was supposed to lower the back end a few inches to facilitate hooking up.

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The air suspension system is always active and keeps the rear of the truck at the same height regardless of load (within limits). The alt trailer height setting lowers the rear of the truck one inch making the truck sit level across its length.

When you select alt height, you will need weight in the rear to force it down, you should see a message in your IPC indicating payload too light. I've read some with 2500s say it will adjust without additional payload but will not on 3500s.

Since the goal of the rear air suspension system is to maintain the truck's rear height based on setting, it will not chase your trailer's tongue. The height should remain the same regardless of the payload applied. If you feel the trucks is chasing your trailer, then see your dealer.

You could try placing it in Tire Change mode. That should stop it from reacting while loading/unloading.

I believe your supposed to put the truck in the jack mode to attach/disconnect a trailer, that includes when your setting your WDH up.
Download the full manual from here:
http://www.ramtrucks.com/en/owners/manuals/

My 1500 with air ride is night and day easier to hook mine up. Entry/exit which is 2 inches lower than stock, back unde the ball via backup camera, then hit raise to off road 1 (plus 3 inches). Get out lock hitch, put wd hitch bars on, hookup brakes, chains and lights. Jump back in truck, put in normal mode and leveling system does its thing.
Not sure how the heavy duties work but good luck getting it figured out.

I've found a lot of info on another Ram forum (turbodiesel) & its full of accounts of the ball "chasing" the coupler up, when offloading. Believe me -it does happen. The suspension system senses the decreased load on the rear and adjusts as you off load. Some say if you leave the eng running, it won't happen. Others disagree. I wish, I wish there was one single source document to explain the various uses of this complex system.

there are several suggestions of this "work around" on Ram turbodiesel register forum. But no mention of it in factory literature.

If you leave the door open will it adjust? On my half ton, if the door is open it won't adjust.

the wealth of info on the Turbodieselregister forum says if any door is open, the system won't work like you need it to for loading or unloading. (it "thinks the eng is off I guess. Several entries say that the engine must be running during load/off load. How practical is that I wonder ? What if you're not able to quickly hitch or unhitch ?) Those entries also say that RAm does NOT recommend "Transport mode "for loading or unloading. Although it stops the up & down movement, it dumps most of the air out of the bags and it could damage the bags by putting weight on them in that condition. Those entries say Ram says use "Tire jack mode" for load/unloading. It stops the system from automatically sensing weight chg's but doesn't dump all the air out. It looks like to me that we're all gona' ave to figure this out ourselves, until Ram publishes a factory guide to loading & unloading using the OEM air suspension . (if any RAM company tech is reading this-pls help us all). I highly recommend reading the entries on TurboDieselRegister. But read all you can because some are diff folks' attempts at figuring it out over time. And all of them didn't work out, but it's a great source on info just the same. Any info, even stuff that didn't work, has helped me.

AS a courtesy here's a copy of the TurboDieselRegister's "authorized" Ram engineers' method of loading & unloading. They collected & published input of 2500 owners and then worked w/ Ram to figure it out.

From the TurboDieselRegister (begin quote) " Ram 2500 Rear Axle Air Suspension

The 2500 system is a rear axle only open air system which fully replaces the rear coil springs of the steel suspension. Ride comfort was enhanced though elimination of the traditional leaf springs on both air and steel suspension offerings. It offers two customer selectable right heights; “normal ride height” and “alternate trailer height”. The latter is intended to eliminate the rake angle of the truck for level towing. The same 3 modes available in the 1500 system (Tire Jack Mode; Transport Mode; and Wheel Alignment Mode) are also available on the 2500 system to modify the system’s behavior and are all intended for the same functions.

Auto Leveling – Time Delay
Like the 1500 system there is an added delay to give a “steel suspension like” behavior. However, with the additional load capacity of the 2500 system, a two stage strategy was developed. When lighter loads are applied the delay time is 10 seconds. Heavier loads will trigger a 20 second delay. Just like the 1500 truck, the engine should be left running when loading the vehicle if auto leveling is desired.

Key Off Strategy
Like the 1500 truck, the 2500 system will also make adjustments to maintain a target ride height after the ignition has been turned off. The air suspension system will stay active for 10 minutes after key off. However, the 2500 system will only lower during this time frame and the compressor is not allowed to run.

Door Open Strategy
Since the 2500 system is a rear axle only system, lowering of the suspension may occur while any door is open.

Trailer Hookup/Unhooking
The alternate trailer height may be used as a way to raise and lower the truck to minimize trailer jacking. The vehicle will always adjust to meet target ride height when using this feature as long as the air suspension system is not being overloaded. However, the following guidelines should be adhered to when hooking up and unhooking a trailer:

When using load distribution bars for conventional towing, select the height you plan to tow at (Ram recommends alternate trailer height) and then adjust load bars as needed (see "Hooking up a Trailer With a Weight Distributing Hitch").
When hooking up or unhooking a fifth wheel trailer, place the vehicle into Tire Jack Mode to prevent automatic height adjustments easing the ability to slide the kingpin out of the head without binding.
Never hook/unhook a trailer or place a load in the bed of the vehicle while it is in transport mode. Transport mode deflates the air bags to lowest safe level possible when selected and the air bags may be damaged by applying additional loads to the vehicle.

Hooking up a Trailer with a Weight Distributing Hitch (all trucks)

Set air suspension to normal ride height. No action is required if already in normal ride height. NOTE: The vehicle must remain in the engine running position while attaching a trailer for proper leveling of the air suspension system. NOTE: For Ram 2500/3500 trucks equipped with rear air suspension, normal ride height or alternate ride height can be used.
Position the truck to be ready to connect to the trailer (do not connect the trailer).
Under radio suspension settings, turn on jack mode. Jack mode will be canceled and procedure must be restarted if the vehicle is driven at speeds above 5mph (8kph).
Measure the height of the top of the front wheel opening on the fender to ground, this is height H1.
Attach the trailer to the vehicle without the weight distribution bars connected.
Measure the height of the top of the front wheel opening on the fender to ground, this is height H2.
Install and adjust the tension in the weight distributing bars so that the height of the front fender is approximately H2-H1)/3+H1 (about 1/3 the difference between H2 and H1 above normal ride height [H1]).
The truck can now be driven. Jack mode will be canceled when driven at speeds above 5mph (8kph).

Request for 2500 Input
Ram truck engineering wants your input on the delays implemented during the auto leveling strategy to provide the “steel suspension like” behavior. When replying please include the following information:

Length of time owning a Ram truck with the factory air suspension system
Typical usage in which you interact with the air suspension (type of trailer being hooked up/unhooked, type of loads going the bed, etc.)
Suggested delay time
Description of why does the delay time need to change or why should it stay the same

Note: This delay is in addition to the amount of time it takes the system to assess the change in height, actual response times to applied loads will vary." (end quote)

What a cluster ****. Glad the 1500 system is more user friendly. And just to show the 1500 system is decent here's a couple pics.

jsummers72 said:

AS a courtesy here's a copy of the TurboDieselRegister's "authorized" Ram engineers' method of loading & unloading. They collected & published input of 2500 owners and then worked w/ Ram to figure it out.

From the TurboDieselRegister (begin quote) " Ram 2500 Rear Axle Air Suspension

When hooking up or unhooking a fifth wheel trailer, place the vehicle into Tire Jack Mode to prevent automatic height adjustments easing the ability to slide the kingpin out of the head without binding.

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Thanks for posting this, interesting information.

What I've isolated doesn't make sense and is not representative of my experiences. I'm wondering if there are various versions of software out that has changed the behavior of the rear air leveling system.

My fiver has the Lippert 6 point hydraulic leveling system and it remembers the height of the trailer when it was disconnected from the truck (which was alt ride height) and I can return the trailer to that position on demand.

When it comes time to hitch, I select the alt ride height and back into the RV's pin box. This forces the rear of the truck down helping it to achieve the alt ride height position, the king pin engages and locks into the hitch. I visually check the king pin is locked and finish the hook-ups. I then retract the RV's landing gear and the rear of the truck lowers slightly. After about a minute or so, the rear of the truck raises to the alt ride height.

If I selected tire jack mode, which disable the leveling system, it would make for a difficult re-hitch since the rear of the truck would not lower from the pin box weight.

When I unhitch, the truck does not raise as I slowly pull away from the fiver disengaging from the pin box. The truck is set to alt ride height, why would it change rear ride height?

I'm not an expert by any means on this subject, I'm hitching the way my dealer showed me using the rear air leveling system. Curious on what others have experienced with hitching a fiver.

yes, it is an interesting problem. During your hook up & unhooking, is the engine running ? That seems to be another variable.

jsummers72 said:

yes, it is an interesting problem. During your hook up & unhooking, is the engine running ? That seems to be another variable.

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Yes, engine running and driver's door open.

Very interesting. Hm-m-m ? All I know about unhooking is that my truck "raised" up as I lifted weight off the ball. Many others recount how theirs did the same. I think it may be semantics. Maybe as you say the truck is not "raising" but what I saw & called "raising" was the truck leveling itself out, which it is supposed to do in all weight/load situations. What ever it was , when unhooking my travel trailer (500 lbs tongue weight) as I cranked up so I could drive out from under the ball, the ball went up w/ my cranking. I was finally able to crank it above the truck's automation "correction" (let's call it), and drive out. For me, maybe using the "tire jack mode" during off loading/unhooking is the secret. Not during initial hook-up. (engine running -is gona' be req'd, I think-ha !) Thanks again everyone

i have 2014 Laramie 2500 4x4. I am having the truck raise as I pull out from under my 5th wheel even when it is lowered by the alt trailer ht button . Where is jack button?

Pumping new life into an old thread...

As I am reading this I am wondering if anyone has any new experience with the RAM 2500 bed lowering mode with the air suspension.

I am assuming that with that mode there is no need to swtich to jack mode, correct? BTW new RAM owner, future TT owner asking.

DIMford said:

Pumping new life into an old thread...

As I am reading this I am wondering if anyone has any new experience with the RAM 2500 bed lowering mode with the air suspension.

I am assuming that with that mode there is no need to swtich to jack mode, correct? BTW new RAM owner, future TT owner asking.

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You use the Jack mode for setting the WDH up(yes contrary to popular beliefs even HD trucks should use WDH).
The bed lowering is just for hooking/unhooking the trailer.

The alt ride height (3500s 1-1+" drop) only works when there is at least 600lbs on the truck or hitch. So, when unhitching, as the load weight decreases the alt ride height disengages.

John Jensen said:

The alt ride height (3500s 1-1+" drop) only works when there is at least 600lbs on the truck or hitch. So, when unhitching, as the load weight decreases the alt ride height disengages.

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Looks like he has a 2500. The alternate ride height in those lowers the backend even with no load. I leave it on when towing one of my trailers, to get it more level. Easier than changing the ball height just for that one trailer. I've never used jack mode, though.