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Poly Performance Upper Shock Bracket Question

5890 Views 34 Replies 9 Participants Last post by  ALASHA
Those of you who are running the rear upper shock relocation bracket (http://www.polyperformance.com/shop...ar-Long-Travel-Upper-Shock-Mount-p-29226.html)

Have you noticed any change in ride quality etc... because the shocks now sit at a steeper angle?

I need to buy new rear shocks and was wondering if I should do this at the same time.
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I don't have any experience with that bracket, but here is my opinion.

When using that bracket you should also use the lower relocation bracket. That should put your shocks back into a relatively stock-oriented position, so your ride quality shouldn't be affected much. On top of that, if you will be ordering new shocks, you would be able to run a longer shock and get more use out of your suspension.
I already have lower shock relocation brackets installed when I did the Rock Krawler Long Arm.

Getting more travel is the game plan considering the current set up maxed out the shocks that I had.
Thanks TCDawg for the input.
TCDawg do the shocks look like they sit at a very steep angle now i.e. alot of pressure on the lower mounting?
The shocks are a little less upright than stock. I don't see any undue pressure on the lower mount.

I'll post some pics when I get home.
That would be awesome. My exhaust is relocated as well so it isnt an issue.
Got a new problem. Went to the Bilstein site to look at lengths for the 5160s. My old shocks had about 10" of travel. The only other size longer has ~11.3" of travel.

With these brackets the additional 2" of upper room is more than what I am gaining by going to the longer shocks not to mention the additional room of moving the shock back.

So now I need to choose a longer shock :suicide:
Ok suspension experts please double check my logic:

All this started because I destroyed my current shocks doing carnage:

I have long arms so I am pretty sure I over extended the shocks. The game plan is to add spring retainers from Currie to keep them from popping out, and these relocations brackets which move the upper mount up 2" and back 2.5" nettting 3.2" of additional shock length based on the pythagorean thereom.

So with that said, I had a 10" travel rear shock. With this bracket, I can go to at least 13" rear travel (maybe 14") which just sounds insane given this is just 2.5" lift.

Am I calculating something wrong or missing something?

I plan to add correct bump stops to prevent over compression and limit straps to prevent over extension.
But you are doing the lowers too right? then you are netting more or am I confused.
Already had the lowers before all of this so the lower mounting position is fixed. We are just talking about the upper now and with long arms, the 10" travel shocks werent enough.
Ok time for some more math. My old shocks were 15" compressed and at ride height showed about 5" of shaft (insert jokes) so 5" of up travel and 5" of down travel. This gives me a total of ~20" of mounting point to mounting point on the shock at rest.

These brackets will give me an additional 3.2" of length as previously mentioned so now the length is 23.2".

With 13" travel Bilsteins, the collapsed length is 18" so at the same ride height I will show 5.2" of shaft again but I will now have 7.8" of down travel instead of the previous 5".

That sounds like ALOT of travel out of a 2.5" lift and will be more than the front set up.

Again anyone see any problems?
You will want to use limiting straps, even if you use spring retainers. With that down travel you may be pushing the limits of your brake line and ABS/speed sensor lines.

so the Bilstiens you are looking at have a compressed length of 18 and an extended length of 31? What model?

Your old shocks were 15 and 25?
Yep limiting straps is part of the plan. I blew out both rear brake lines so new ones need to be ordered anyway. Didint think about the speed sensor lines.

I had the 5160s for a shorter lift so 14.9"/25" is the collapsed/extended length.

Unfortunately, the 5160s only come in 2 sizes so I need to change to the 5165s which will require me to change the upper mount over to a bar pin which Bilstein says is easy. The valving isnt identical but its really close.

All info is here:
Which valving are you going with? Is 13" travel more than springs typically will handle before dropping out of the buckets in the rear?
So I got it up on a lift last night without any shocks in it, the distance between mounting locations for the shock is 26". This distance is fixed by the length of my tone ring wires and the length of my sway bar links.

At this point I am at a loss. I can stick with the stock upper mount location and get the same shocks which will give me 5" up travel and 5" of down travel. The up travel and down travel will be a little less because of bump stops and limit straps but the 5" down still leaves ~1" of that full 26".

Or I can get the next size up of 5160s which would give me 4" up travel and 7" down. Again both will be a little less because of bump stops/limit straps but the 7" now is 1" more than the full 26".

Going with the Poly brackets doesnt net me anything unless I get longer links and extend the wires. Not sure I really want to do all that...
the speed sensor/tone ring wires can be extended pretty easily. It is just a regular wire. Cut, solder in an extension, button it back up....at least that what it looks like. I have not done the extension but I did cut open an old wire to check it out and it looked like a regular wire.
Yeah its not super hard but the bracketry is ~$200 so the question is do I want to spend that and do the wires/sway bar links to get minimal gains.

Considering I already need to buy brake lines, bump stops, limiting straps, spring retainers, shocks and drive shafts I am a little more reluctant to buy the bracketry now :(
Your math may be off just a bit since the shocks are not vertical and your up and down travel will be different then the amount of shaft showing. And don't the upper brackets move the top mount farther away from the axle? Keep an eye on your pinion angle and u-joint bind as well at the new droop. You may need a limit strap at the differential as well.

Your axle does not move straight up and down either, it moves in an arc towards the center of the jeep as you droop it out. Tall short arm lifts will move quite a bit eating up shock travel with them in the stock mounting configuration.
Right all my numbers were based on shaft movement, not exactly equal to wheel travel because of the angles.

Yes the upper bracket moves the mounting location up 2" and back 2.5"
Were you unhappy with the way it was before?
If not just replace the shocks and make sure your bumpstops and limit straps are setup properly.
I have read a post from bilstein that says overextending a shock at slow speeds(rock crawling) should not damage the shock but it looks like at least one of yours got bent.
I have a very similar setup to you minus the long arms and the 10" travel 5160s work well with 2.5" coils.
Nope I am happy with the current set up. I just wanted to explore my options given the fact that I need to buy new shocks anyway.

Both my shocks are bent.

A long arm 2.5" lift should have very little movement forward at the axle and if the mount moves up and back by those amounts you should be able to run a shock that has 2" more travel then what you have now while maintaing the same amount of up travel.

Extending the abs is as simple as just splicing in a new longer wire. If you don't want to worry about brake lines you can run them down one of the upper control arms and you will not have to worry about stretch. I did this as well as running the abs wire down the upper arm.
So doing the math, after extending the lines and sway bar links, I can get 3" additional of droop minus limit strap reduction.

As for running the lines, I have a single upper and fear that the zip ties would rub against the gas tank and after enough time would rip. Not a major issue but still a concern
What does bilstein charge to rebuild the 5160s?
So a basic rebuild is $75 per shock plus shipping. I have bent shafts so that is an additional $30 per shock.

The worst part is that they are on a ridiculous back log. I was told a minimum 4 week wait time.
Why not rebuild yourself. It is pretty easy to do. The only special tool you will need is to get the ISP out if needed and you can make it out of all thread. Just buy the rebuild kits. I do my own king shocks. They are all pretty much the same.
I dont really have the skill set to do it and I banged up one shock body pretty bad so I dont think that one can be rebuilt.

I spoke with Jeremy from Rock Krawler and I think I am going to go with the next size up 5160 which will give me more droop.
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