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'21 3500 Rear Air Suspension - Smoooth Ride!

CdnHO

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That's the way it is on 3500. Mine does the same as do many others. Some don't see any or near as much.

The claimed 2-3 in some videos are a reference to the 2500 with full air suspension.

You need to remember that the 3500 air suspension is supplemental, unlike the 2500.

The only real way to solve any of this is to go full air on the 3500, or perhaps a man-in-the-middle sensor fooler, like the pedal foolers that can be adjusted on the fly.
I like the idea of some sort of sensor “fooler”.
 

gimmie11s

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Any one tried using one of the after market ride height adjustable sensor rods on the rear if a 5th gen dually? I would like the truck a little lower with the fifth wheel on it. Clearance is a bit short.

Couple guys on the forum have them. This is the way to go for adjustability.

 

kxnate

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After putting a level kit on my 3500 SRW with Air, I’ve had a thought regarding the Alt Trailer Height and also the Bed Lowering abilities. We are discussing keeping the airbags “deflated” for a better ride and adjusting sensors so they stay that way empty. BUT in my experience so far, the bed lowering doesn’t really work like the RAM informational video shows. And the Alt Trailer height may also be affected if the bags are not inflated prior to activating either of those systems?
When I tap on bed lowering, my bed only drops about an inch (maybe)...

Thoughts?

I did a 0.5” level kit in the front and my truck is sitting slightly higher in the front now, hoping it just needs to settle in a bit


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The bags do nothing on a 1ton when empty, the leafs are too stiff. I took measurements on mine while trying the bed lowering mode and I barely got 3/16" drop when unloaded. Where the auto level bags shine on a 1 ton is when you do this, 3400 lbs of water in the back.20210522_143835.jpg
 

Brutal_HO

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The bags do nothing on a 1ton when empty, the leafs are too stiff. I took measurements on mine while trying the bed lowering mode and I barely got 3/16" drop when unloaded. Where the auto level bags shine on a 1 ton is when you do this, 3400 lbs of water in the back.

Very true. I meant to add to the post that I carry extra gear in the truck and feel it's just enough to allow it to lower about 3/4" but rushed the reply.
 

CdnHO

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CdnHO

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Very true. I meant to add to the post that I carry extra gear in the truck and feel it's just enough to allow it to lower about 3/4" but rushed the reply.
I am only interested in the truck being lower with the fiver on it. I realize the springs will keep it at normal ride height when unloaded.
 

joesetum

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The bags do nothing on a 1ton when empty, the leafs are too stiff. I took measurements on mine while trying the bed lowering mode and I barely got 3/16" drop when unloaded. Where the auto level bags shine on a 1 ton is when you do this, 3400 lbs of water in the back.View attachment 16682
So when loaded the air bags make it go back to stock ride height with forward rake? My truck on order is the same layout at yours, CCLB with air suspension. Was wanting to see if I could get away with leveling the truck without it sagging while towing
 

Brutal_HO

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So when loaded the air bags make it go back to stock ride height with forward rake? My truck on order is the same layout at yours, CCLB with air suspension. Was wanting to see if I could get away with leveling the truck without it sagging while towing

FWIW, the air equipped 3500 only rake about 1" or so as opposed to the non-air trucks 2-3". That's why Alt Trailer height only lowers it 1".
 

kxnate

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So when loaded the air bags make it go back to stock ride height with forward rake? My truck on order is the same layout at yours, CCLB with air suspension. Was wanting to see if I could get away with leveling the truck without it sagging while towing
Yup, as soon as you start putting weight to it the bags pump up and level it out. My truck does not seem to have a whole lot of rake to it loaded or empty. It's really pretty level already. If you look at my above pic, there is 3400lbs of water in the truck and zero squat if you look at the wheel well gaps. My old 05 1 ton Cummins was squashed to the overloads with this load.
 

kxnate

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FWIW, the air equipped 3500 only rake about 1" or so as opposed to the non-air trucks 2-3". That's why Alt Trailer height only lowers it 1".
I wondered if they pulled some rake out of the air suspension trucks. Like I mentioned above, mine seems pretty level empty.
 

Brutal_HO

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I am only interested in the truck being lower with the fiver on it. I realize the springs will keep it at normal ride height when unloaded.

Agree. that's what Alt Trailer Height is for.

Probably we've discussed this before, bed lowering mode is intended for hookups (not that kind) and cancels when driven over 8(?)MPH. As also covered, some get the bed lowering drop, some don't. I think it's partly the trim level sprung weight and gear load in the truck. You also can't engage Alt trailer Height if you're moving (forget the speed) and as is also widely known, without a load (estimated ~600lbs.)

Sorry if you've heard it before and I'm repeating, these threads start to melt together after a while.
 

Brutal_HO

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I wondered if they pulled some rake out of the air suspension trucks. Like I mentioned above, mine seems pretty level empty.

Removing the overload spring (or two?) and replacing with the the bags and softer (?) springs certainly makes the whole package different. I suspect it's the way the combination worked out. No reason to build in the rake that's going to get used up by a load when you can just pump air to supplement/correct.
 

loveracing1988

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FWIW, the air equipped 3500 only rake about 1" or so as opposed to the non-air trucks 2-3". That's why Alt Trailer height only lowers it 1".
I have regular leaf springs in my 2020 3500 and I only have 1.5" of rake.
 

roegs

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Last weekend I finally put the truck to work towing a new to us 5th wheel home ('19 Grand Design 2930RL). Stopped at the CAT scale on the way home. Pin weight was just under 2500 lbs and I was 600 lbs under my GVWR of 11,800 lbs. I knew this would exercise the rear suspension and after disconnecting the 5th wheel, noticed that my right (passenger) air bag was firm. Suspension must have settled a bit. Just as I'd done on the drivers side, I loosened the height sensor bolts and turned it slightly. The bag released its pressure. The amount I turned it was slight and just based on the mounting holes a little larger than the mounting bolts. My theory (and again, I could be incorrect) is that these 3500 trucks should have no air in the bags when the truck is empty and full of fuel. That allows the truck to take advantage of the lighter spring pack used with this air suspension system.
 

Brutal_HO

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Last weekend I finally put the truck to work towing a new to us 5th wheel home ('19 Grand Design 2930RL). Stopped at the CAT scale on the way home. Pin weight was just under 2500 lbs and I was 600 lbs under my GVWR of 11,800 lbs. I knew this would exercise the rear suspension and after disconnecting the 5th wheel, noticed that my right (passenger) air bag was firm. Suspension must have settled a bit. Just as I'd done on the drivers side, I loosened the height sensor bolts and turned it slightly. The bag released its pressure. The amount I turned it was slight and just based on the mounting holes a little larger than the mounting bolts. My theory (and again, I could be incorrect) is that these 3500 trucks should have no air in the bags when the truck is empty and full of fuel. That allows the truck to take advantage of the lighter spring pack used with this air suspension system.

That may improve the ride but will most certainly neuter the bed lowering mode and explain why some have it and some don't.

I always ran 5 PSI in my aftermarket, even after replacing the original bags/rusted out rollplates with the (stainless) bump stop version. Good deal for the guy that bought my truck one year later. :)
 

CdnHO

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Last weekend I finally put the truck to work towing a new to us 5th wheel home ('19 Grand Design 2930RL). Stopped at the CAT scale on the way home. Pin weight was just under 2500 lbs and I was 600 lbs under my GVWR of 11,800 lbs. I knew this would exercise the rear suspension and after disconnecting the 5th wheel, noticed that my right (passenger) air bag was firm. Suspension must have settled a bit. Just as I'd done on the drivers side, I loosened the height sensor bolts and turned it slightly. The bag released its pressure. The amount I turned it was slight and just based on the mounting holes a little larger than the mounting bolts. My theory (and again, I could be incorrect) is that these 3500 trucks should have no air in the bags when the truck is empty and full of fuel. That allows the truck to take advantage of the lighter spring pack used with this air suspension system.
on the passenger side did you move the sensor clockwise? or counter clockwise?
 

roegs

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That may improve the ride but will most certainly neuter the bed lowering mode and explain why some have it and some don't.
Not sure I'm following....can you clarify? Bed lowering only comes into play when there is sufficient load on the rear suspension.
 

roegs

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on the passenger side did you move the sensor clockwise? or counter clockwise?
LOL...I was afraid that someone might ask me this question. I always have to think it through. I believe the sensor gets turned counter clockwise to command less pressure for a given height.
 

Brutal_HO

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Not sure I'm following....can you clarify? Bed lowering only comes into play when there is sufficient load on the rear suspension.

Alternate Trailer Height (to level) requires a load.

Bed Lowering Mode is something different, it dumps all air from the bags.

The two are distinct features that use the air suspension.

My truck will lower the bed pretty consistently around 3/4". It is somewhat dependent on the fuel level and what's in the truck.
 

roegs

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Alternate Trailer Height (to level) requires a load.

Bed Lowering Mode is something different, it dumps all air from the bags.

The two are distinct features that use the air suspension.

My truck will lower the bed pretty consistently around 3/4". It is somewhat dependent on the fuel level and what's in the truck.
Interesting....will it let you drive in that mode? I should probably clarify that when I made the slight adjustments to the sensors I could easily push my fingering the side of the bag (as opposed to it being firm). There very well could be a few pounds in them.
 

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