Replacement shock absorbers on a 4-corner air-suspension Ram.

[E.Hands]

@E. Hands, any more feedback on the swap? Any modifications necessary like it seems was required (shims) on the 4th gens? I'm looking at swapping 5100's on my front shocks since I've got 5100s on my rears already. Part number I'm looking at is 24-300872. Replacing the rears really helped the ride at 106k miles on my Limited. Now I'm realizing my fronts need swapped pretty bad. Hoping the extra grooves on the fronts will keep me away from needing to purchase the special ones with the groove machined in that special spot.

Only other feedback is, when you get it done, you will be happy that you did it.
And pleased with the money that you saved doing it!

 

[Loganator456]

Only other feedback is, when you get it done, you will be happy that you did it.
And pleased with the money that you saved doing it!

Thanks! Only question I have, or what I'm worried about, is potentially having to charge the system & whatever costs/dealer headaches that may entail. My air ride seems to be working just fine right now.
The standard step I'm seeing is to take the suspension down to entry/exit to keep the most amount of air in the system, not the shocks. Anything else you had to do?

 

[E.Hands]

Thanks! Only question I have, or what I'm worried about, is potentially having to charge the system & whatever costs/dealer headaches that may entail. My air ride seems to be working just fine right now.
The standard step I'm seeing is to take the suspension down to entry/exit to keep the most amount of air in the system, not the shocks. Anything else you had to do?

That's exactly what I did. And obviously you don't want to do it under extremely humid conditions, like while it is raining.
Once you have removed the air line's flare nut, you may hear a slight pressure release. Then back out the brass fitting on top of the shock. This will allow any residual pressure out and will allow the shock to fully compress during it's removal process.
I used a long pry bar to remove the shock from between the LCA (lower control arm) and the frame.
There was no need to remove the LCA.

Understand that if the system needs more air volume to work with once operational, it will simply take in outside air as needed.
So don't turn on the ignition until everything is buttoned back up.

 

[Loganator456]

That's exactly what I did. And obviously you don't want to do it under extremely humid conditions, like while it is raining.
Once you have removed the air line's flare nut, you may hear a slight pressure release. Then back out the brass fitting on top of the shock. This will allow any residual pressure out and will allow the shock to fully compress during it's removal process.
I used a long pry bar to remove the shock from between the LCA (lower control arm) and the frame.
There was no need to remove the LCA.

Understand that if the system needs more air volume to work with once operational, it will simply take in outside air as needed.
So don't turn on the ignition until everything is buttoned back up.

Your feedback and experience sharing through all this is greatly appreciated. Once I do the swap I will post here and share my experience/results. Thanks!!

 

[E.Hands]

Your feedback and experience sharing through all this is greatly appreciated. Once I do the swap I will post here and share my experience/results. Thanks!!

You 're quite welcome!
I'm curious, have you tried different settings on the 7793 ?
Where do you currently have it set?

 

[GSD222]

Thanks! Only question I have, or what I'm worried about, is potentially having to charge the system & whatever costs/dealer headaches that may entail. My air ride seems to be working just fine right now.
The standard step I'm seeing is to take the suspension down to entry/exit to keep the most amount of air in the system, not the shocks. Anything else you had to do?

If you have access to a tank of nitrogen it's actually not that hard to charge the system if needed. Dropping to entry/exit should get the job done but if you need to refill for whatever reason after the fact you'll just need the n2, a vacuum pump, and an a/c manifold gauge set, both of which you can probably borrow for a deposit from your local auto parts store. Even easier if you have Alfaobd because you can check the system pressure after the fact as well. I had to do it a couple times recently because the leak I had in my system wasn't obvious initially.

 

[OCD Solutions]

Just got a shipment notice for my OEM shocks so it looks like the nationwide back order may finally be over.

 

[1BADRAMLIMITED]

I see those listed as a 74 pound tire, stock size Michelin is listed as 39 pounds.
You are asking the stock shock to deal with a lot more load.
So picture how much force is needed to change the direction of 39 pounds at arms length. Now double that weight and change direction with it.
I would go with the higher dampening.

I’m new to trucks and knew a lot changes when adding a level and bigger tires. I will be getting the 5100’s soon. I did see from the article the other member posted referencing 4600 vs 5100 that there is a 5100 that is not adjustable. Are the adjustable 5100’s better if you are going for a level or which part # is the non adjustable 5100?

 

[Loganator456]

You 're quite welcome1
I'm curious, have you tried different settings on the 7793 ?
Where do you currently have it set?

I've tried all of them and swapped back & forth a ton. My preferences differ based on how nit picky I'm feeling about ride quality, tire pressures, etc. With worn shocks and lower tire pressures (32-34 cold), I liked the tightest position. Crazy good body control but definitely stiffens the ride - before replacing any shocks, at 36 psi or higher on wornish factory-style tires, the ride was harsh. Middle setting with worn shocks was perfect.

If I had new but relatively soft shocks (think Foxes) I would probably keep it as tight as possible. I'm riding on the softest setting now. Not a fan of how loose it feels (probably slightly better than bone stock), my worn tires and front shocks have me fatigued and it's something I can live with until the fronts are replaced. Replacing the rears w/ 5100's helped both with ride & body control perspective so I don't need the bar doing as much work. The Bilsteins are stiffer but I'm also wanting bigger tires so it's a long-term investment.

Dream setup would be (air ride or otherwise) - TRX style wheel tire combo (18's with softer-ply 35's, maybe narrower - more sidewall if anything), soft but new shocks (Fox style), and the 7793 at mid or tight setting. Whatever gets me the best combination of both super smooth ride and decent handling. I am nitpicky in general (if you haven't noticed) so that's my fault for being in love with a platform with limited options.

 

[OCD Solutions]

Well, my OEM front shocks arrived today so I can confirm, the cheaper $110 Bilsteins will not work, even if I move the circlip. I think we could have determined this had we looked at the dimensions but seeing them side by side, it is glaringly obvious in seconds that they aren't compatible.

So, here are side by side pics of the OEM Bilstein option, (P68323489AD) and the cheaper option the we questioned if it would fit, (24-329132).
The most obvious differences are that the unit for our air ride suspension has a smaller tube diameter, shorter tube and shorter shaft.

I'll be swapping the shocks out tomorrow so I will take more pics with all 3 shocks side by side for the ultimate reference but I believe that option is adequately debunked.

*Another difference to point out, the cheaper shocks are assembled in Mexico, the ones for the air-ride are assembled right here in USA.

 

[E.Hands]

Well, my OEM front shocks arrived today so I can confirm, the cheaper $110 Bilsteins will not work, even if I move the circlip. I think we could have determined this had we looked at the dimensions but seeing them side by side, it is glaringly obvious in seconds that they aren't compatible.

So, here are side by side pics of the OEM Bilstein option, (P68323489AD) and the cheaper option the we questioned if it would fit, (24-329132).
The most obvious differences are that the unit for our air ride suspension has a smaller tube diameter, shorter tube and shorter shaft.

I'll be swapping the shocks out tomorrow so I will take more pics with all 3 shocks side by side for the ultimate reference but I believe that option is adequately debunked.

*Another difference to point out, the cheaper shocks are assembled in Mexico, the ones for the air-ride are assembled right here in USA.

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Thanks for that data!
The 24-329132 is very different. I'm shocked (no pun) that the tube diameter is different though.
In your picture it looks like diameter of the polished rod is different too, is this true? Or is the 24-329132 that has the larger O.D.s?
All of the lengths seem longer on the 24-329132 I was hoping this would be an easy "lift kit" swap. But evidently not.

It will be interesting to see how your factory shock compares to these two side by side.

 

[OCD Solutions]

The Polished rod is larger on the OEM Bilstein but it is the same diameter as the little bushing on the factory shock so the end result is the same. The threads are identical too but the picture makes the factory unit look much smaller than it actually is.



I had already boxed up the Bilstein test model so I didn't bother doing any further comparisons with it.

 

[E.Hands]

The Polished rod is larger on the OEM Bilstein but it is the same diameter as the little bushing on the factory shock so the end result is the same. The threads are identical too but the picture makes the factory unit look much smaller than it actually is.

View attachment 187953

I had already boxed up the Bilstein test model so I didn't bother doing any further comparisons with it.
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Nice work area!
I still find it hard to believe that all of the vehicle's weight is supported by just that snap ring.
Do you think that the air bag pushes on the upper shock tube's body or top end?
I do see a small taper to the upper couple of inches of of the tube's O.D.

 

[OCD Solutions]

Install went pretty smooth this morning. I started a little before 6am and was wrapped up around 11am, and that included me breaking for about an hour to make some breakfast and tend to the wife.

I noticed a bit more road noise than usual during the test drive but otherwise it was smooth and exactly what I would expect from Bilsteins. I'll find out tomorrow if this resolves my strange issue with a vibration at speed but I have a feeling it will. As other's have noted, 3 out of the 4 shocks all retracted when disconnected except for the passenger front; it was the only one trying to fully extend, and I actually had to disconnect the UCA to get that one out. I suspected this was the source of my problem all along so it was interesting to find that this shock acted differently than the rest. I did a side by side compression and release test and the drivers side was fully extended 2-3 seconds ahead of the passenger side.

There were a couple surprises that were not previously mentioned that I wish I was prepared for but I worked them easily enough. Mostly on how the shock is inserted and sealed into the air assembly. 1st, how to remove it and then how to reseat it against the circlip again.

Removal is easy enough, place the assembly top down on a piece of plywood or other anti-marring surface and use a piece of wood or other other material to drift the aluminum collar down and off the body of the shock. To reseat the shock into that collar, I assembled the top part of the shock completely and then aired it up with my compressor. It all popped into placed with about 85lbs of air.



I removed the lowest stainless retainer and pulled the boot back just enough to expose the lip of the lower collar so i didn't damage it.


This is how it looked upon re-assembly.



The other item worth noting is that there is a tapered bushing/spacer inside the bag assembly that you need to verify is aligned before you insert the new shock. It's an orangish color and I just used a long screwdriver to align it.



Some B-shots for fill....

 

[OCD Solutions]

Nice work area!
I still find it hard to believe that all of the vehicle's weight is supported by just that snap ring.
Do you think that the air bag pushes on the upper shock tube's body or top end?
I do see a small taper to the upper couple of inches of of the tube's O.D.

That clip certainly sees some load but I think it may be distributed using the central aluminum shell pictured below. The lower tapered section sits and seals against the circlip but the top of the shock body also inserts into a formed section in the upper part of that same aluminum shell to hopefully put some load on the top of the tube itself.



This is where i questioned the difference in the shape of top of the tubes. If this surface seats into that aluminum shell, will the sharp surface of the Bilstein sit differently than the rounded factory unit? Time will tell but I don't really see it being an issue.

 

[OCD Solutions]

Put 400 miles on the truck this morning and it is back to riding like a luxury vehicle again. It's like you don't know how worn out your running shoes are until you slip into a new pair.

It didn't solve all my vibration issues but it's worlds better so I think part of it is the road itself plus a few minor issues with my tires still that don't show up below 80MPH.

 

[Loganator456]

OCD, your write up has been excellent. If I could play devil's advocate, what do you think would actually prevent the cheapo Bilstein option from working? Is is just a matter of the dimensions/machined groove being different, or would there not be enough room for you to assemble the bag assembly back onto the new strut? I wouldn't think the thinner OD of the strut body would make too much of a difference as long as it came with a snap ring or clip.
What would the impact be if one just assembled it onto the different shock anyways?

Glad to hear your fix has done you well. Looking forward to doing the same myself.

 

[OCD Solutions]

The issue is that the shock body slides up into the assembly and forms the seal to keep the air inside. It's not just a hollow cavity with ample clearance that the shock just feeds through. So if the shock body is even fractionally larger, it simply won't fit. Too narrow and it wouldn't ever seal.

I didn't detail it well or take any pictures of it but there is a thin tapered collar and O-ring seal that slides over the tube body and rests on top of that circlip.
*You will want to clean all surfaces and lubricate it well before assembly so when you insert the shock into the aluminum shell, it has enough slip to fully insert and make a good seal without tearing the O-ring. I found enough residual assembly oil left inside the tube to re-use for this purpose. Some lubricants will react to rubber and swell or break them down so best to not introduce any unknowns to this equation without doing some research first.
**The new shock does not come with any of these parts so you will have to transfer it all from the old shock.

I have illustrated what this stack up looks like below. Note that the seal area is deep enough that I don't believe it actually bottoms the O-ring out. The sealing area is over 1/2" deep where-as the circlip, collar and O-ring are probably no more than 1/4" total. This means that the circlip just holds the seal in place and there isn't any weight of the truck actually applied or sitting on it.



In this pic, you can see three detents in the top recess, this is where the top of the shock tube will insert and rest against those 3 tabs.
* The orangish rubber piece you see offset inside is what I believe to be a rubber bump stop to protect the internals if the assembly is ever fully compressed. Like if you blow a line and the assembly bottoms out.

 

[OCD Solutions]

I found this illustration detailing the Land Rover Air Suspension. It's not exactly the same as our RAMs but it's close enough to give you an idea of what the internals look like.

 

[E.Hands]

I found this illustration detailing the Land Rover Air Suspension. It's not exactly the same as our RAMs but it's close enough to give you an idea of what the internals look like.

View attachment 188068

Very interesting. I didn't remove the bellows dust cover at all, so I never got to see that detail. Thanks for sharing!
The way that our set up is designed, the seal around the polished rod it the top of the tube is exposed to the air pressure inside air bag.
Where as the "spring" type shock only sees atmospheric pressure.
Just a thought, but perhaps this could be a difference in the two designs. Airbag shock vs Spring shock.
As a seal that holds pressure in one direction is very different from one that controls pressures in both or in the opposite direction (think "cup" type seals).

I'm not sure how much pressure is inside a Bilstein but if the airbags pressure was higher and entered the shock body, the it may cause the shock to extend out. Then the computer would sense the increased ride height and begin lowering the suspension... something to ponder.