How to set your bump stop on a Jeep Wrangler TJ

I planned on adding extensions on the bottom, but why are extensions preferred in the rear? Can I do bottom extensions in the rear as well?
For the rear, the springs are wide enough that an extension from the top won't cause the jounce bumpers to "pluck" the spring coils when extended. It is much easier to add the extension to the top (rear only) as all you need is a longer bolt vs drilling and tapping to lower perch.

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For the rear, the springs are wide enough that an extension from the top won't cause the jounce bumpers to "pluck" the spring coils when extended. It is much easier to add the extension to the top (rear only) as all you need is a longer bolt vs drilling and tapping to lower perch.

View attachment 144376

Makes sense. My only concern with that is I won't know the length needed for the bump stop, until I do all of this. I'd like to to have an adjustable one, so I can do this once and be done. Plus, I like consistency, so I'd prefer to use the same front and rear. As long as it's okay to do so.
 
I can do this once and be done. Plus, I like consistency, so I'd prefer to use the same front and rear.
I can understand liking consistency. The extensions I bought from Mike (in my writeup) are the same material (UHMW-PE) but are slightly different sizes in terms of diameter and height. Also front extension on the bottom and rear on the top is very much the accepted way of doing this.

BTW - My Jeep was down for a week while I waited for them to arrive but neither of my TJs are my daily driver and this one's been down for 14 months now as I go thru all major mechanicals. Although it took a week, this was a "one and done" effort and way cheaper than adjustables.
 
Makes sense. My only concern with that is I won't know the length needed for the bump stop, until I do all of this. I'd like to to have an adjustable one, so I can do this once and be done. Plus, I like consistency, so I'd prefer to use the same front and rear. As long as it's okay to do so.
Completely okay. You can add extension to the bottom on both the front and the rear.
 
@T A I bought a set of 4 (front and rear) made by Fairchild from summit. Was around $30 shipped if I recall correctly.

Whatever brand you choose, make sure you buy the OEM style. I first bought a set of poly bumpstops but sent them back as there is zero compression in them. The bump stops need to fully compress into the cup or you will lose uptravel in your suspension.
 
Hey!

Tomorrow I am installing my 2" lift. OME Springs + Rancho Shocks. I am setting my bump stops too. It's my first time.

Just to be clear. Is this photo from post #1 correct?
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1) Should I remove the jounce bumper and measure the distance between the cup and the spring pad? Then add an extension in order for this distance to be slightly smaller than shock up travel length? (Does jounce bumper fully compress really?)

2) Does the same apply for the rear as well? Should I remove the jounce bumper for the rear too and measure like the front?

Any help would be appreciated since in about 8-9 hours I am installing it. @jjvw I would really need your input on that!
 
The jounces do compress completely into the cup. Remove it along with the springs when cycling the axle. Bring the axle all the way up until the shocks are fully compressed. Add extension to bring the cup closer to the axle pad. Treat the rear the same way.

If the tire or something else gets in the way of compressing the shock you have to clear obstruction or change to a shock with a longer compressed length.

Your goal is to fit a shock with the most travel that divides that travel in half at the normal ride height.
 
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