Problem with new Rancho RS5000X shocks


Daredevil96

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Question about these rancho shocks...

I had previously purchased the front rancho RS5000x in February. They felt SOOO NICE. Now I knew I needed rear shocks as well so I recently got the rear to match the front and for some reason they feel EXTRA BUMPY. It’s like they’re over dampening. I know I got the correct shocks. I measured the lift a while back and it was a 3 inch lift. The rear rancho RS5000x part number I got was the RS55256 from 4 wheel drive.

When I got the shocks, I noticed that they looked fairly new but they came in a different box. I don’t know if it was a return or something from someone and rancho fixed them, maybe there was an issue with them before I don’t know. But I got them installed at a shop, first thing I heard when I drove off was a couple of noises as if something was hitting, or bumping into things. Then that went away (I’m assuming they were adjusting) but it definitely feels like it’s over dampening

the jeep jumps up and down and I did not have that problem before. I’m wondering if they need to be broken in for a little bit? Has anyone had that issue before?
 
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Daredevil96

Daredevil96

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That definitely sounds like the new replacement rear shocks are simply too long for your suspension lift height.
Last time I checked, I had a 3 inch lift. I got this Jeep in February. Can I still measure the lift height even with these new shocks installed just to double check? I know you can subtract the difference of the spring height minus the stock height which I believe is 8 inches for the rear.
 

mrblaine

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Last time I checked, I had a 3 inch lift. I got this Jeep in February. Can I still measure the lift height even with these new shocks installed just to double check? I know you can subtract the difference of the spring height minus the stock height which I believe is 8 inches for the rear.
Just post up a picture from the rear showing how much shock shaft is showing at ride height.
 
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Daredevil96

Daredevil96

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I am not home but I can post a picture once I get there. I asked the guys at the shop that installed it and they said they had to be extended to fit? So this has me wondering what is going on.

Is there a chance when I first measured it, the shocks had been busted already? and I measured the rear with a busted shock and maybe it gave me wrong lift height
 

freebo86

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Because when they are supposed to compress they are fully bottomed out and can’t compress enough.
I do not understand this at all. I’m trying to visualize it but can’t...

So a too long shock would have a longer body and longer shock travel. It sitting on the Jeep level on level ground the shaft travel would be more exposed vs. a proper sized shock.. driving down the road and hitting a bump you’d use some shock travel but there would be more than needed left.. vs. the properly sized shock. What am I not understanding here?
 

mrblaine

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I do not understand this at all. I’m trying to visualize it but can’t...

So a too long shock would have a longer body and longer shock travel. It sitting on the Jeep level on level ground the shaft travel would be more exposed vs. a proper sized shock.. driving down the road and hitting a bump you’d use some shock travel but there would be more than needed left.. vs. the properly sized shock. What am I not understanding here?
You can't because he confused you. When a too long shock is installed, you have LESS shock shaft that can move into the body to damp the axle movement upward. The axle only has to move a small amount upward before it bottoms out and and transfers the road event to the chassis instead of damping it. That is perceived as a harsh bumpy ride because it is.

What you described is a shock that is too short even though you said it has a longer body and longer shock (shaft) travel.
 

Jerry Bransford

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What you described is a shock that is too short even though you said it has a longer body and longer shock (shaft) travel.
Put another way, its available travel is too short and it bottoms out well before it should. Not that the overall shock length is too short. When the shock is too long you have to compress it more to make it fit which uses up much of its available travel.
 
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freebo86

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You can't because he confused you. When a too long shock is installed, you have LESS shock shaft that can move into the body to damp the axle movement upward. The axle only has to move a small amount upward before it bottoms out and and transfers the road event to the chassis instead of damping it. That is perceived as a harsh bumpy ride because it is.

What you described is a shock that is too short even though you said it has a longer body and longer shock (shaft) travel.
Put another way, its available travel is too short and it bottoms out well before it should. Not that the overall shock length is too short. When the shock is too long you have to compress it more to make it fit which uses up much of its available travel.
Believe it or not I’m still confused. I would assume a too short shock would bottom out sooner than too long shock when installed in a incorrect application.

So can a too short shock cause the same issue? Rough ride etc?
 

jjvw

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Believe it or not I’m still confused. I would assume a too short shock would bottom out sooner than too long shock when installed in a incorrect application.

So can a too short shock cause the same issue? Rough ride etc?
The shorter the shock travel, the shorter the compressed length. A shock that is too short will run out of extended length and try to lift the axle off the ground.

The longer the shock travel, the longer the compressed length. The longer shaft needs to fit somewhere. A shock that is too long will run out of compression and try to push the axle into the ground.

Adding spring lift increases the measured distance between the frame side and axle side shock mounts. This will stretch the existing shock and disrupt the ideal 50/50 travel distances from the normal ride height. Increasing this distance between mounts requires a longer shock to rebalance the shock travels at the normal ride height.

Many aspects of building a suspension get easier if you can learn to pay close attention to the compressed lengths of the shocks.
 
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mrblaine

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Believe it or not I’m still confused. I would assume a too short shock would bottom out sooner than too long shock when installed in a incorrect application.

So can a too short shock cause the same issue? Rough ride etc?
You should quit trying to make what we are saying translate into what you believe. It is very clear you are not trying, you have a preconceived notion of how shocks work and it is entirely backwards from reality.

Let's start with the basics.

What is the compressed length of a shock?
 
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