What Difference Do Shocks Make?

Late to the party, but this is my experience:

I switched from Fox 2.0 to RX5000.
It wasn't a terrible switch, but i wouldn't do it again.
RX5000 are softer riding, no argument, but they are too soft for my liking. Jeep turned from being firm and confident on the road, to a wooshy- mooshy floating couch. It is as if im riding on a water bed.

Overall, Jeep is more wobbly, steering became more sensitive to road imperfections. Bump stops are bottoming out on the intersection humps i used to ride over without issues.

I understand that most people on here are older than me, and more sensitive to a rough ride due to age or injuries... but, i cant recommend something as soft as RX5000.
On other hand, what else is there?
That right there shows how different people like different rides. I used to like the soft ride of cheap hydro shocks. Of course they did not do well on bigger bumps, but I didnt drive like I do now back then.

I've come to prefer the ride of a firmer shock, better road manners. Of course there's a balance of not being harsh, and when you open it up on the trail you want a shock that will also flow enough oil and not have too much rebound to be harsh.

I've tried the RS5000x on a TJ, my SUperDuty, and just put them on the wife's JK (want3ed the Kings but recent circumstance killed the budget). I've found they have a nice medium ride on the TJ, way too soft for the SuperDury, and are actually surprisingly firm (in a good way) on the WK. I think they'll break in to be good on that Jeep.
 
I have read this thread a couple of times and realize the differences in opinions, but would like to ask about a little different comparison. My TJ has Rancho 9000 on the rear and Bilstein 5100 on the front. The rear 5100's blew out. The OP installed the 9000's because he couldn't get replacement Bilsteins (under warranty) for 60days. My wheeling is 90% street, but many of my streets are fairly rough, with many being gravel roads (lots of washboard) and 10% old mining trails with some rocks. I have a 3inch lift with 1.15inch BL and 33's. Would it be better off with another set of 9000's in the front or just go with 5000x?
I've found the RS9000 to be too harsh on TJ personally. But if you like the way they ride, then you're the only one to tell you that. The 5000x will definitely be softer.
 
I was always told nitrogen wont fluctuate in pressure through a temperature range as much as air would. But these were not chemists telling me this so I dont know.
i read info that stated nitrogen is just as susceptible to temp fluctuation as regular old air.

the way i understood it was the molecules do not dissipate through the tire, or in the shocks case the seals, like some of the smaller molecules in air can do. that the dissipation of those smaller molecules is what causes the fluctuations.
next it's clean and dry your not risking interior contamination like air might carry in.

technically you could use any inert gas, IIRC.
 
I was always told nitrogen wont fluctuate in pressure through a temperature range as much as air would. But these were not chemists telling me this so I dont know.
Mr. Boyle has a few things to say about that. He even made it into a law. At the pressures we deal with, for a given rise in temperature, all gases expand at exactly the same rate. Also, "air" is very subjective. If it is air from a very humid area, that will not be the same expansion rate as air from a very dry area. Moisture content creates big problems.

For the moisture side, most of the gases we deal with are pulled out of frozen air. They take air, compress it, pull off the heat, and keep doing that until it is a liquid. Liquid gases have very low temperatures, couple of hundred degrees or so below the freezing point of water. That means any water in there is a solid. All gases boil off at different temperatures. So, they raise the temp up to the level for a specific gas and boil it off to collect that gas out of the mix. Still way below the point water freezes at so it stays solid.

In other words, it isn't possible to get water into the various compressed gases simply due to how it is separated out of air.
 
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i read info that stated nitrogen is just as susceptible to temp fluctuation as regular old air.

the way i understood it was the molecules do not dissipate through the tire, or in the shocks case the seals, like some of the smaller molecules in air can do. that the dissipation of those smaller molecules is what causes the fluctuations.
next it's clean and dry your not risking interior contamination like air might carry in.

technically you could use any inert gas, IIRC.
You're correct. The only reason we use inert gases is to prevent some of the bad reactions that can occur over very long use intervals. Short term would not be a problem for most of them.
 
I have read this thread a couple of times and realize the differences in opinions, but would like to ask about a little different comparison. My TJ has Rancho 9000 on the rear and Bilstein 5100 on the front. The rear 5100's blew out. The OP installed the 9000's because he couldn't get replacement Bilsteins (under warranty) for 60days. My wheeling is 90% street, but many of my streets are fairly rough, with many being gravel roads (lots of washboard) and 10% old mining trails with some rocks. I have a 3inch lift with 1.15inch BL and 33's. Would it be better off with another set of 9000's in the front or just go with 5000x?
Measure the shocks at their mounting points at ride height. Pick a shock that will give you as close to 50/50 bias as you can based on ride height.
 
That right there shows how different people like different rides. I used to like the soft ride of cheap hydro shocks. Of course they did not do well on bigger bumps, but I didnt drive like I do now back then.

I've come to prefer the ride of a firmer shock, better road manners. Of course there's a balance of not being harsh, and when you open it up on the trail you want a shock that will also flow enough oil and not have too much rebound to be harsh.

I've tried the RS5000x on a TJ, my SUperDuty, and just put them on the wife's JK (want3ed the Kings but recent circumstance killed the budget). I've found they have a nice medium ride on the TJ, way too soft for the SuperDury, and are actually surprisingly firm (in a good way) on the WK. I think they'll break in to be good on that Jeep.
I have miss typed RX5000 for RS5000x, either way you are spot on.
Unfortunately this is one of those things that you have to try it in order to understand, there is simply to way to explain to someone what is soft and what is harsh.

I liked my Foxes, only reason why i switched is because they have a weird gap in lift size for the front shocks, one part number maxes out at 2" of lift, and another is too big for anything below 3.5" ( even though they state it is for 3 - 4.5").

This is my dilemma, ya the fox ifp are way too stiff but they’re also incredibly controlled on the street so long as it’s a perfectly smooth road lots of bumps cause the rear to get loose pretty easily, they’re so stiff I get very little body roll without a front sway bar. I don’t want a land yacht ride either though.

Which is why I’m planning to make the jump to the custom tuned smoothies. Rather than wasting more money on off the shelf shocks. It’s a big leap in price but I’m not planning on ever selling my tj and I’m at the ride height I wanna stay at.
^ Fughudert finds IFP Foxes to be too stiff.

For me, if i were to use 1- 10 scale, RS5000x is the softest at #10 as it should get. If anyone needs anything softer than that, they need another vehicle with independent front suspension.
Foxes would sit at #7ish on my scale compare to RS5000x.
If i could find something that can be put into #8 slot on my imaginary scale, i think they would be a perfect compromise in between just soft enough to remove harsh rattle, and stiff enough to offer stability and not have a "water bed" effect.


@pcoplin
your experience on 3 different vehicles makes me wonder how consistent this shocks are, because being medium on TJ, soft on SD and firm on JK , and here i am labeling mine as a floating couch ... doesn't make much sense 🤨
 
I've found the RS9000 to be too harsh on TJ personally. But if you like the way they ride, then you're the only one to tell you that. The 5000x will definitely be softer.
Is there a direct correlation to firmness/softness and how it affects travel or can you tune to have the best of both worlds? For example, you have two drivers with 100% identical setups. Driver A likes a soft "cloud" feel and Driver B prefers a firm planted feel. Is it possible for both drivers to get what they want and still be able to use all of the available travel or will the soft one bottom out and the firm one never use the travel?
 
Is there a direct correlation to firmness/softness and how it affects travel or can you tune to have the best of both worlds? For example, you have two drivers with 100% identical setups. Driver A likes a soft "cloud" feel and Driver B prefers a firm planted feel. Is it possible for both drivers to get what they want and still be able to use all of the available travel or will the soft one bottom out and the firm one never use the travel?

Just to muddy the waters, go back to what I said about the Fox tune compared to the AllTech. It's almost like they are valved oppositely of each other. With the Fox, they ride more like a cloud, but to get there you have to get past the jitters. Whereas the AllTech soaks up the small road noise, but is a much firmer shock overall. And I can easily use all of the travel going to the grocery store if I want to. This is actually the far superior tune.
 
I do not like the RS55255 5000x on the front. The front is showing about 5.25" shaft which is close to half. My main complaint is too much high speed dampening on small sharp bumps. The rear RS55256 has about 4.25" shaft showing on a 9.6" travel shock. The rears feel like they are under damped in all situations. The front feels like a one ton pick up and the rear like a 70s Cadillac and I don't like either. I do see me with tuned shocks before New Years.

I have done some tuning on motorcycle shocks and forks so I kind of know what is involved. How much does it cost in tools, shims etc to DIY tune shocks? I wouldn't think a full shim kit would be necessary just for personal use. If anyone knows of places that has good info for Fox tuning, please post the website.
 
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I do not like the RS55255 5000x on the front. The front is showing about 5.25" shaft which is close to half. My main complaint is too much high speed dampening on small sharp bumps. The rear RS55256 has about 4.25" shaft showing on a 9.6" travel shock. The rears feel like they are under damped in all situations. The front feels like a one ton pick up and the rear like a 70s Cadillac and I don't like either. I do see me with tuned shocks before New Years.

...

Funny. My RS55255 5000x fronts have close to 6" of shaft exposed and they still feel like they are under damped. Yet that is the compromise for not having a jittery shock.
 
I do not like the RS55255 5000x on the front. The front is showing about 5.25" shaft which is close to half. My main complaint is too much high speed dampening on small sharp bumps. The rear RS55256 has about 4.25" shaft showing on a 9.6" travel shock. The rears feel like they are under damped in all situations. The front feels like a one ton pick up and the rear like a 70s Cadillac and I don't like either. I do see me with tuned shocks before New Years.

I have done some tuning on motorcycle shocks and forks so I kind of know what is involved. How much does it cost in tools, shims etc to DIY tune shocks? I wouldn't think a full shim kit would be necessary just for personal use. If anyone knows of places that has good info for Fox tuning, please post the website.
Its a couple of hundred bucks to get started.

To fill the shocks You will need...

Regulator

Hose

access valve

As well as a nitrogen bottle from your local supplier. I spent $130 for a small bottle.

You can get shims from polyperformance. They sell them in stacks labeled #30, #60 #90 etc. There is a chart on their site to convert those numbers to shim thicknesses. It's about $15 a stack. Get the goat built thing that helps you hold the spacers on when installing shocks.

Here is a good guide to get you started:
CrawlPedia

And here is a good video for a shock rebuild. He rebuilds a king, but foxes are the same. Pay special attention to the bicycle pump trick ... Unless you want shock oil on the ceiling. *Probably add shock oil to the list of things you will need. Just sayin

 
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Its a couple of hundred bucks to get started.

To fill the shocks You will need...

Regulator

Hose

access valve

As well as a nitrogen bottle from your local supplier. I spent $130 for a small bottle.

You can get shims from polyperformance. They sell them in stacks labeled #30, #60 #90 etc. There is a chart on their site to convert those numbers to shim thicknesses. It's about $15 a stack. Get the goat built thing that helps you hold the spacers on when installing shocks.

Here is a good guide to get you started:
CrawlPedia
So .. If I can revalve shocks, I can buy anything in 2" with the correct extended and compressed length, then set them up for my Jeep, right? There seem to be a lot of guys around me selling Foxes off their bro-dozers for cheap. Might be worth picking up the stuff to tune them, if I can get the right shocks at the right price.

If I understand properly, it's only the factory shocks that you can tune and rebuild, right? The performance ones are more difficult?
 
So .. If I can revalve shocks, I can buy anything in 2" with the correct extended and compressed length, then set them up for my Jeep, right? There seem to be a lot of guys around me selling Foxes off their bro-dozers for cheap. Might be worth picking up the stuff to tune them, if I can get the right shocks at the right price.

If I understand properly, it's only the factory shocks that you can tune and rebuild, right? The performance ones are more difficult?
Correct, all fox 2.0 factory shocks have the same valve shims.

The performance ones can be rebuilt and re-valved as well. They use the same part numbers for shims and seals. However, they don't use a standard Schrader fill valve like the Performance series. You need one of these...

https://www.amazon.com/dp/B0714L5LTL/?tag=wranglerorg-20

I called fox and asked if the body of the shock could be drilled and tapped to accept a normal Schrader valve, they said absolutely, its not common, but people do it if they need to re-valve or rebuild frequently. The reason most companies don't mess with them is the needle adapter is fragile and expensive and the shock is kinda considered disposable because of thier lower cost. The internals are all the same.
 
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Correct, all fox 2.0 factory shocks have the same valve shims.

The performance ones can be rebuilt and re-valved as well. They use the same part numbers for shims and seals. However, they don't use a standard Schrader fill valve like the Performance series. You need one of these...

https://www.amazon.com/dp/B0714L5LTL/?tag=wranglerorg-20

I called fox and asked if the body of the shock could be drilled and tapped to accept a normal Schrader valve, they said absolutely, its not common, but people do it all the time if they need to re-valve frequently. The reason most companies don't mess with them is the needle adapter is fragile and the shock is kinda considered disposable because of its lower cost. The internals are all the same.
If the internals are the same, what about it makes it lower cost? Something about the bodies? No adjusters?
 
If the internals are the same, what about it makes it lower cost? Something about the bodies? No adjusters?
The body is extrude formed the same way an aluminum gas cylinder is made. That makes the top eye, inlet area, hose attachment, and body all one piece so that minor machining has to be done to turn it into a shock.

The steel versions have a machined and finished body that is plated, machined top cap with eye all of which add cost.

The extruded bodies also suffer from not being perfectly straight and not being made from steel so if they do wear, it happens fast.
 
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I was always told nitrogen wont fluctuate in pressure through a temperature range as much as air would. But these were not chemists telling me this so I dont know.
That is what the FAA and the US Air Force has claimed in their maintenance training for decades.
 
If the internals are the same, what about it makes it lower cost? Something about the bodies? No adjusters?
The internals are also quite a bit different. Piston is quite a bit smaller with different free bleed, and the seals are different. Plus the aforementioned aluminum bodies. All around less expensive shock.
 
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