Coil springs bump stop

In your picture, the jounces are rotted away. That is not the bump stop. All that part is meant to do is act as a cushion before the steel cup smacks the axle pad. The jounce will compress into the cup. Replace them with the new yellow part you found.

You do have some extension. That is the cleaner black plastic cylinder just above the cup.
 
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In your picture, the jounces are rotted away. That is not the bump stop. All that part is meant to do is act as a cushion before the steel cup smacks the axle pad. The jounce will compress into the cup. Replace them with the new yellow part you found.

You do have some extension. That is the cleaner black plastic cylinder just above the cup.
In the pictures above does it look like I am missing the bump stop on the bottom?
I have a 3.5" lift with 33x12.5 R15 tires. Can you guesstimate how much bump stop I would need if you think I'm missing that on the bottom? Or is the bottom cup just supposed to be flat? I mean I don't see any bump stops on any of my coil springs front or back. They can't all just be gone can they?
 
Nothing is missing. The cup is the upside down cup shaped piece of metal hanging down from the frame. That axle pad is the flat round pad on top of the axle tube.


How long is that plastic cylinder?
What is the compressed length of the shock?
Do you have a body lift?

The lift height is irrelevant to the amount of required bump stop.

Post a pic of the rear bump stops.
 
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Here are some examples of my extended bump stops over the years.
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Alright man, let's try to do some math. The length of my tower from bottom of metal to right where the joust would stick out is 9". Between there and the metal plate is about 6". That's not including where the jounce bumper would stick out. Now between the top of my tire and fender is 6" roughly. I'll post some pictures
 
For clarity, as the Jeep sits in the driveway, what is the amount of space between the cup and pad? What is the amount of exposed shock shaft?
 
Would I need much bump stop extension for the rear if I'm doing a 2.5 lift and just 2" extensions for the fronts with my flat Fenders?


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The answer most likely depends on your tire size and compressed shock lengths. Lift height is irrelevant. Cycle the suspension to find out what your front and rear interferences are. Add bump stop extension to prevent these interferences.

Flat fenders do not create any more room than stock, unless they are Metalcloak or a true highline where the hood is cut.
 
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For clarity, as the Jeep sits in the driveway, what is the amount of space between the cup and pad? What is the amount of exposed shock shaft?
The space between the cup and pad is 6" minus the joust
The amount of exposed shock is 7"
So if I'm thinking this right it really shouldn't need more than 1" maybe 1.5"?
The odd thing is I can't see where a bump stop would have been mounted
 
The space between the cup and pad is 6" minus the joust
The amount of exposed shock is 7"
So if I'm thinking this right it really shouldn't need more than 1" maybe 1.5"?

This is progress. The shock is protected from over compression. How long is that plastic cylinder above the cup? That is your bump stop extension. The next question to answer is if it is long enough to keep the tires from mashing into the steel fenders when the axle is at full flex. Like this...
72c2cb90547860f1b96db2434aed4c05.jpg


466add3a7f7680cc47af69e60a63bc31.jpg


Too much extension is better than not enough extension. Not enough extension is as good as no extension.

The goal is to have just enough extension to keep parts from crashing into other parts, but not too much as to unnecessarily limit the suspension's up travel.

The odd thing is I can't see where a bump stop would have been mounted

If you were to remove that plastic cylinder, you would return the bump stop back to its factory configuration. What you see is what you get.

The extension can be added in two places. Above the cup, like yours. Or to the axle pad, like mine. The important part is to reduce that open space between the cup and the pad.
 
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...
The odd thing is I can't see where a bump stop would have been mounted

Just had this thought that might be helpful. The cup is bolted to the frame mount. The bolt is accessed by removing the jounce.

Whoever extended those bump stops also added a longer bolt along with the plastic extension.

With yours being old and rotten, you will need to dig and chisel them out to get to the bolt head.
 
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The answer most likely depends on your tire size and compressed shock lengths. Lift height is irrelevant. Cycle the suspension to find out what your front and rear interferences are. Add bump stop extension to prevent these interferences.

Flat fenders do not create any more room than stock, unless they are Metalcloak or a true highline where the hood is cut.

Thank you I want to be positive before I put this next lift on and my tire size is 255/75r17 so about 31-1/2 or 32 and the shocks I bought have Compressed Lengths of 14.010; Extended Length: 22.290; Travel Length: 8.280 I have 2" bump stops laying around that I was going to add guess cycling everything wouldn't be a bad idea


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This is progress. The shock is protected from over compression. How long is that plastic cylinder above the cup? That is your bump stop extension. The next question to answer is if it is long enough to keep the tires from mashing into the steel fenders when the axle is at full flex. Like this...
View attachment 48942

View attachment 48943

Too much extension is better than not enough extension. Not enough extension is as good as no extension.

The goal is to have just enough extension to keep parts from crashing into other parts, but not too much as to unnecessarily limit the suspension's up travel.



If you were to remove that plastic cylinder, you would return the bump stop back to its factory configuration. What you see is what you get.

The extension can be added in two places. Above the cup, like yours. Or to the axle pad, like mine. The important part is to reduce that open space between the cup and the pad.
Now that you said the bump stop could be at the top as opposed to the bottom this all makes sense. So if my exposed shock is 7" but maybe only compresses to SAY 5". Then all is good in the hood lol. I don't need axel pad bump stops. Just a new joust bumper. How far out does the joust bumper sticker out? Thanks for making this all clear to me. That's alot of geometry scientific sideways thinking. Lol
20180727_104643.jpg
 
The jounce sticks out 2" from the cup. But keep in mind that it is designed to compress into the cup. The space between the cup and pad is what matters.

Your shocks are safe. However, the 8" measurement between the tire and fender is not the full story. When the axle flexes, as seen in my pics above, it pivots around the compressing spring. The tire will rise higher into the wheel opening than your measurements suggest.
 
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... guess cycling everything wouldn't be a bad idea


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Cycling is the only way to know. Anything else is a guess. And if you are guessing, be sure to guess on the long side.

Cycling the axle allows you to select the optimal length extension as well as the optimal length shocks for your specific combination of modifications.
 
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The jounce sticks out 2" from the cup. But keep in mind that it is designed to compress into the cup. The space between the cup and pad is what matters.

Your shocks are safe. However, the 8" measurement between the tire and fender is not the full story. When the axle flexes, as seen in my pics above, it pivots around the compressing spring. The tire will rise higher into the wheel opening than your measurements suggest.
My passenger front coil spring slipped off the axel pad and is now resting on the axel :/ does that mean I need a new spring? Or can i just put it back right?
20180727_111416.jpg
Musta lost a retaining clip. If I do need a new springs how do I measure for that? When I take the spring off? Just length and width?
My lift is 3.5" spring in place is 15.5".