Shocks and Struts

[ITSNO60]

Anyone upgraded/replaced them on the 3500? I am looking at Koni red for the front, they make one with adjustable damping that a lot of Sprinter guys rave about and a newer one that supposedly automatically adjusts for different conditions. For the rear I am looking at Fox 2.5s custom tuned by a shop in CA and are reportedly very good at reducing roll and sway. Just curious if anyone here has experience with these brands or if not what did you go with.

[Bgibbs]

I highly recommend Bilstein.

[Bruce B]

If I were going to change shock absorbers and switch from the factory parts, I’d stick to a single brand front and rear.
After many years in the automobile repair industry, I still question the decision to “upgrade” to aftermarket brands unless you have some very specific needs.
Mercedes (remember this is Mercedes, the German manufacturer who over engineers just about everything!) does a lot of testing of the vehicle to determine the best damping characteristics for the shocks.
Now, if you are using a vehicle in a manner for which it was not optimized, all bets are off. Now it is up to you to figure out what is better suited for your use.
Be aware though, every single parameter you change will be a trade off.
Want the compression damping a little firmer to tighten the feeling of turn in? You will feel it in every bump of the road.
I’ve installed a lot of “must-have-the-latest-best-shocks/struts in customers vehicles only to remove them a year later when they finally admitted that they weren’t really all that nice to live with on a daily drive...
There is a reason that high end sports cars have the ability to change damping characteristics from sport to something softer for real life...

[ITSNO60]

Originally Posted by Bgibbs

I highly recommend Bilstein.

Thanks Bgibbs, I have looked at the Bilstein and they are still a consideration

[ITSNO60]

Originally Posted by Bruce B

Now, if you are using a vehicle in a manner for which it was not optimized, all bets are off. Now it is up to you to figure out what is better suited for your use.
Be aware though, every single parameter you change will be a trade off.
Want the compression damping a little firmer to tighten the feeling of turn in? You will feel it in every bump of the road.

This is pretty much where I am at, it is a cab chassis build with an 11 foot tall Class A MH on it weighing just over 10K dry and just over 11K loaded. Being a Class A the cab was cut down to the windshield base and dash extended forward a couple feet. The handling at speed and in wind leaves a bit to be desired although part of that could be 56K miles on the original equipment, although it is commonly agreed by other owners of the same units that the OEM parts are not up to the job.
I appreciate your input as I am concerned about the trade off between max damping and ride. Your input makes me consider the self adjusting version a bit more which promise a slightly better ride. I do not expect a Cadillac ride on a MH by any means and safety is the main goal here.

[RoadJager]

+1 Bilstein.

[Bruce B]

Originally Posted by ITSNO60

This is pretty much where I am at, it is a cab chassis build with an 11 foot tall Class A MH on it weighing just over 10K dry and just over 11K loaded. Being a Class A the cab was cut down to the windshield base and dash extended forward a couple feet. The handling at speed and in wind leaves a bit to be desired although part of that could be 56K miles on the original equipment, although it is commonly agreed by other owners of the same units that the OEM parts are not up to the job.
I appreciate your input as I am concerned about the trade off between max damping and ride. Your input makes me consider the self adjusting version a bit more which promise a slightly better ride. I do not expect a Cadillac ride on a MH by any means and safety is the main goal here.

OK, you understand the issues...
I have always liked Bilstein shocks too.
Oh by the way, I am sure that with 56,000 miles on them, the original dampers are no longer performing the way they did when new. I’ll, have to read up on the new Koni auto adjusting shocks...sounds interesting.

[ITSNO60]

Originally Posted by Bruce B

OK, you understand the issues...
I have always liked Bilstein shocks too.
Oh by the way, I am sure that with 56,000 miles on them, the original dampers are no longer performing the way they did when new. I’ll, have to read up on the new Koni auto adjusting shocks...sounds interesting.

Thanks, I'll look forward to hearing what you think of them. I described them as self adjusting but more accurately Koni refers to them as having Selective Damping Technology. http://www.koni.com/en-US/Cars/Produ...pecial-Active/

[Bruce B]

Originally Posted by ITSNO60

Thanks, I'll look forward to hearing what you think of them. I described them as self adjusting but more accurately Koni refers to them as having Selective Damping Technology. http://www.koni.com/en-US/Cars/Produ...pecial-Active/

If you search a bit, you will find that Edelbrock made shock absorbers utilizing similar claims. I have no idea if the technology is the same but it sounds similar.
Ford used them on my 2010 F-150. They rode well but routinely failed. After 40,000 or so miles and a bunch of failures, I finally switched to Bilstein 4600’s and never looked back. The ride was stiffer but controlled.

[ITSNO60]

Originally Posted by Bruce B

If you search a bit, you will find that Edelbrock made shock absorbers utilizing similar claims. I have no idea if the technology is the same but it sounds similar.
Ford used them on my 2010 F-150. They rode well but routinely failed. After 40,000 or so miles and a bunch of failures, I finally switched to Bilstein 4600’s and never looked back. The ride was stiffer but controlled.

I have the Bilsteins on my F-350 and I love the ride.

[Tronadora]

Originally Posted by ITSNO60

Anyone upgraded/replaced them on the 3500? I am looking at Koni red for the front, they make one with adjustable damping that a lot of Sprinter guys rave about and a newer one that supposedly automatically adjusts for different conditions. For the rear I am looking at Fox 2.5s custom tuned by a shop in CA and are reportedly very good at reducing roll and sway. Just curious if anyone here has experience with these brands or if not what did you go with.

Knowing that you would like to hear from Airstream Interstate owners, not truck owners, I can offer up my qualified opinions. I have 49,000 miles on my 2015 3500 based Interstate, I replaced all shocks at 23,000. Koni Golds in back that I am happy with and Koni Red self adjusting shocks in front that are definitely an improvement over stock but still have too much bounce. I would like to replace the fronts only with Bilsteins. In a passenger car I would agree with the user about keeping the brands the same, but in this rig I have no problem doing a mix and match. The load characteristics are so different front to back.

[ITSNO60]

Originally Posted by Tronadora

Knowing that you would like to hear from Airstream Interstate owners, not truck owners, I can offer up my qualified opinions. I have 49,000 miles on my 2015 3500 based Interstate, I replaced all shocks at 23,000. Koni Golds in back that I am happy with and Koni Red self adjusting shocks in front that are definitely an improvement over stock but still have too much bounce. I would like to replace the fronts only with Bilsteins. In a passenger car I would agree with the user about keeping the brands the same, but in this rig I have no problem doing a mix and match. The load characteristics are so different front to back.

Thanks, good info. Have you considered the manually adjustable Koni struts?

[Tronadora]

I inquired about manually adjustable Koni for the front and was told by more than one shop they do not exist for this vehicle. Sigh. Supposedly the automatic load compensation feature built in is supposed to satisfy me but it does not. It's still a big improvement, just not as good as I think it could be.

[Hawk-ination]

I completely disagree with the statement that Mercedes would have tuned the ride in the best way and that exploring aftermarket products is a mistake. They may have optimized our Sprinters to ride well before adding thousands of pounds and tweaking the center of gravity in the Sprinter. Being in the automotive aftermarket, I've helped hundreds of customers fine tune their vehicles with brands and products that improve and/or enhance the ride or function of their vehicle. I've sold everything to truck lifts and low rider kits, and especially tuner kits from back in the day when Fast and Furious was popular and cool.

I also see no reason not to mix product lines on the Sprinter. There's plenty of members who have installed different products along with different shocks and sway bars, the front end does not have the same function as the rear.

I have not upgraded the suspension yet, so I do not have experience to offer and will leave that to those who have. I hope you get good advice from Interstate owners who have upgraded because learning from others who have done the mods already can help make the right decision for what you want to accomplish. After all, most parts are made by the aftermarket companies you are looking at buying from and who provides the product characteristics to the manufacturer.

[Bruce B]

Originally Posted by Hawk-ination

I completely disagree with the statement that Mercedes would have tuned the ride in the best way and that exploring aftermarket products is a mistake. They may have optimized our Sprinters to ride well before adding thousands of pounds and tweaking the center of gravity in the Sprinter. Being in the automotive aftermarket, I've helped hundreds of customers fine tune their vehicles with brands and products that improve and/or enhance the ride or function of their vehicle. I've sold everything to truck lifts and low rider kits, and especially tuner kits from back in the day when Fast and Furious was popular and cool.

I also see no reason not to mix product lines on the Sprinter. There's plenty of members who have installed different products along with different shocks and sway bars, the front end does not have the same function as the rear.

I have not upgraded the suspension yet, so I do not have experience to offer and will leave that to those who have. I hope you get good advice from Interstate owners who have upgraded because learning from others who have done the mods already can help make the right decision for what you want to accomplish. After all, most parts are made by the aftermarket companies you are looking at buying from and who provides the product characteristics to the manufacturer.

I made my advice about mixing and matching after selling many millions of dollars of service to automobiles over many years.
I too saw people lift, lower, level, stiffen and otherwise modify suspensions, add “tuners” and a whole pile of other aftermarket modifications.
While there are modifications that “improved” things for people, most had very sharply defined trade offs.
Nobody spends as much understanding a vehicles dynamics as the manufacturer of the vehicle. If you believe that Mercedes has not accounted for the weight added to this chassis you are simply wrong. Now, you may not like something about it and you may decide to mix and match products to “correct” that but there will be trade offs. Understanding them before plucking your $ down is the tricky part...
This is a little like listening to people review their new tires on a vehicle. By the time you need tires, any new tire will probably feel good! This you get the “the vehicle just felt far better...” review.
Of course it did! This applies to shocks and struts in the same way.

[ITSNO60]

Originally Posted by Tronadora

I inquired about manually adjustable Koni for the front and was told by more than one shop they do not exist for this vehicle. Sigh. Supposedly the automatic load compensation feature built in is supposed to satisfy me but it does not. It's still a big improvement, just not as good as I think it could be.

They do exist, for both the 2500 and the 3500 (They can only be adjusted off the vehicle) https://www.sprinterstore.com/produc...sprinter-3500/

[Rocinante]

Hmm...I'm more of a "set and forget" kind of person when it comes to shocks in my vehicles. I just want the best possible overall ride right out of the chute, no messing around, no worrying about it, because for me, looking at, thinking about, and adjusting shocks and suspension as I go is the opposite of interesting.

Given that, what do you see as the best solution for a 2016 Interstate 3500 GL? I'd want less rolling back and forth when going over curbs or bumps, a better ride in back, and a nice responsive front end that also gives a good ride.

Our van only has about 40K miles on it so the stock suspension should theoretically have many thousands of miles left to go, but if we were to upgrade to achieve the objectives above, what would you suggest? There are plenty of folks singing the praises of their Agile Offroad RIP Kit suspension upgrades, though that outfit is quite far away from us at the moment.

[Hawk-ination]

Well Bruce, I guess we need to politely agree to disagree on this point. If you think that Mercedes builds their chassis to add the additional weight our Interstate, I find your reasoning very puzzling. Why then are some (maybe most) of us Interstate owners searching for solutions for the needed upgrades in ride and control quality?

You really think they design the shocks and springs to ride at optimal stance and quality at an almost max weight?? What happens to the Sprinter that doesn't have the weight that our RVs do? What about the alignment issue many of us have run into because "Mercedes optimally set our alignment correct" for the added weight of our RVs? I'm sorry, I do not want to get into specifics but I'm not sure if you don't understand how a suspension works or maybe how a suspension works with tons of added weight, or where you are coming from.

May I point out that it's not only Airstream owners that are looking for improvements to the ride and control of their RVs with the Sprinter van chassis. I'm actually curious if you've ever rode in an Interstate yourself.

If you disagree that owners shouldn't mix and match, I think you should look at the specific suggestions and mods that previous interstate owners have made. Look at the Sumo spring combos with sway bars, etc.

I just think if you are going to hand out suggestions, you should have a better background of what you are talking about. Just don't think you are giving good advice tying your experiences into a situation I don't believe you are completelyY understanding. Possibly your "millions of dollars of sales" were of products that didn't work for your customers because you didn't investigate what your customer wants as a result and match the product to that specific need or want. You don't own an Interstate, at least by your profile, and I respectfully doubt that you know what these people are talking about or searching for in these upgrades unless you've been in the driver's seat. I'd invite you for a ride in our Interstates and then in a Sprinter that has not been modified and then lets talk about how our Interstates handle or don't handle.

To the original post, there are quite a few discussions out there if you search for them. On a different group, I've seen a couple people discuss what sounds like the best combination that the owners have shared being happy we results to date that I've read about so far. It's a shop in Florida called Sprinter Van City in Ft. Pierce, FL that addresses shocks, leaf springs, and ride height and body roll. The owners mention to talk to Eric and that they claim to have installed this combo on 350 chassis in five years.

I've read quite a few posts regarding upgrades and it seems many owners have tried one or two of the three. You'll see they will comment on improvements, but I've only seen a couple where the owners really rave about their results. The only few I've seen who talk about pretty stellar results have recommended the shop I am referring to. I think the key is in not only in the shocks, but in beefing up the leaf springs, which makes sense with the additional weight our Interstate mods add to the original Sprinter chassis. Sorry, I strongly disagree with Mercedes having tuned our ride already.

Much respect to those of you who have made improvements and might have different results to share. Always learning along the way.

[Tronadora]

On the topic of leaf springs, I do have specific information that people might be interested in. At the recommendation of my local Sprinter specialist (mail order as well as a working shop) that I will not name, I removed the horrible Sumo Springs (that another Oregon Sprinter mail order specialist had recommended) and replaced them with BOSS airbags (CANNOT recommend) and a lift kit comprised of two leaf springs added on each side in the rear. HUGE mistake there too. (I kept the new Koni Golds in place on the rear).

We immediately departed for a cross country trip and cussed and swore over every bump at this "solution". I had to keep the airbags inflated to 30lbs plus or minus to keep them from banging top and bottom plates together. The extra leaf springs also made things just way too stiff. By Illinois we could bear it no longer. My galley cabinets had also begun separating from the ceiling. We had one leaf removed from each side. The ride improved but was still not at all satisfactory, very jarring, loud bangs over bumps. In Maine we had the other leaf spring removed for another improvement but those damn airbags were still a huge problem. Upon return to Oregon, I had the airbags removed and have been reasonable happy ever since. Lesson learned: do ONE product upgrade at a time.

I sold the Sumos and airbags on Ebay. The leaf springs went to the metal recycling graveyard. We consistently travel nearly full with 6900lbs rear and 4000lbs front with average tank levels around 50%. In other words, full gas, zero to half fresh water, low as possible grey and black.

[Bruce B]

Originally Posted by Hawk-ination

Well Bruce, I guess we need to politely agree to disagree on this point. If you think that Mercedes builds their chassis to add the additional weight our Interstate, I find your reasoning very puzzling. Why then are some (maybe most) of us Interstate owners searching for solutions for the needed upgrades in ride and control quality?

You really think they design the shocks and springs to ride at optimal stance and quality at an almost max weight?? What happens to the Sprinter that doesn't have the weight that our RVs do? What about the alignment issue many of us have run into because "Mercedes optimally set our alignment correct" for the added weight of our RVs? I'm sorry, I do not want to get into specifics but I'm not sure if you don't understand how a suspension works or maybe how a suspension works with tons of added weight, or where you are coming from.

May I point out that it's not only Airstream owners that are looking for improvements to the ride and control of their RVs with the Sprinter van chassis. I'm actually curious if you've ever rode in an Interstate yourself.

If you disagree that owners shouldn't mix and match, I think you should look at the specific suggestions and mods that previous interstate owners have made. Look at the Sumo spring combos with sway bars, etc.

I just think if you are going to hand out suggestions, you should have a better background of what you are talking about. Just don't think you are giving good advice tying your experiences into a situation I don't believe you are completelyY understanding. Possibly your "millions of dollars of sales" were of products that didn't work for your customers because you didn't investigate what your customer wants as a result and match the product to that specific need or want. You don't own an Interstate, at least by your profile, and I respectfully doubt that you know what these people are talking about or searching for in these upgrades unless you've been in the driver's seat. I'd invite you for a ride in our Interstates and then in a Sprinter that has not been modified and then lets talk about how our Interstates handle or don't handle.

To the original post, there are quite a few discussions out there if you search for them. On a different group, I've seen a couple people discuss what sounds like the best combination that the owners have shared being happy we results to date that I've read about so far. It's a shop in Florida called Sprinter Van City in Ft. Pierce, FL that addresses shocks, leaf springs, and ride height and body roll. The owners mention to talk to Eric and that they claim to have installed this combo on 350 chassis in five years.

I've read quite a few posts regarding upgrades and it seems many owners have tried one or two of the three. You'll see they will comment on improvements, but I've only seen a couple where the owners really rave about their results. The only few I've seen who talk about pretty stellar results have recommended the shop I am referring to. I think the key is in not only in the shocks, but in beefing up the leaf springs, which makes sense with the additional weight our Interstate mods add to the original Sprinter chassis. Sorry, I strongly disagree with Mercedes having tuned our ride already.

Much respect to those of you who have made improvements and might have different results to share. Always learning along the way.

Wow...
I am sorry if I’ve struck a sore spot here.
I only point out what my experience is to hopefully prevent someone from taking the trip down the “Primrose path” of free internet advice without stopping to think about the big picture.
I have read many really interesting things online. There are people who believe many things who have the ability to type them out. That means exactly nothing...
When I look for advice, I look to those who have real credentials born of intelligence, education and experience who hopefully have not got a vested interest in my decision. That’s not an easy thing to find.
I suppose I pointed out my history in the auto business to show that my experience was based not on a single bad event but on many. I wanted my customers to be informed and happy with the work we provided. I believe that you can say that we were successful for the most part by doing our utmost to give them realistic expectations.
When people came in asking that the latest KYB single tube shock be installed in their Saab 900, I’d show them pictures of broken Lower A frames and describe the ride that they would experience here in our frost heaved, pot holed part of the world. Yes, the car would “feel” better in turn-in events but at a great cost. The same KYB shocks had the impact of loostening the entire vehicles interior including the dash to the point that after a year the cars rattled terribly. Maybe those shocks were perfect in California where roads were better but they were a disaster here in New England.
I saw hundreds of internet driven “fixes” that were pretty awful.
Certainly there were good ideas and items that helped tremendously too.
After many years in the shop, I’ve learned that any single thing can be improved upon. It can be a simple “blueprinting” to get it closer to the design spec due to sloppy manufacturing or it might be a replacement with a different design to address a weakness. Manufacturers do this all the time.
The trick is in being able to discern the difference and the impact not only on the micro level but rather on the macro level.
I will say this again, if you suggest that Mercedes Benz hasn’t designed the vehicle for the purpose intended and does not know/understand/care about its being used with this weight for this purpose, you are wrong.
If you want to base your experimentation on the advice given in forums... I wish you luck. Design by committee is a real thing.