Rear Shock Placement

I was wondering some about the rear lower shock mounts on the xj and what their placement has effect on the suspension. A while ago I did my 8.8 swap and welded my new tabs on as double shears up on the axle tube so they don't hang down and make the shock angle about vertical. Now that I thought about it more I noticed when I pulled the 8.8 it had this stupid looking 3rd shock than ran angled to the axle off the center section. I just relized it must have been for side to side movement with the leaf springs and wondered if the factory angle of the xj shocks has a similair effect and if would improve handling over my vertical placement setup. whats your ideas and opinions?

The biggest problem with moving your shock mounts up that high is that with the same shock, it limits up travel. All in all, it limits your flex since you can only put so long a shock on due to the limited space.

The mounting arrangement of the stock shocks does have a slight stabilizing effect on the axle but probably not enough to warrant changing your mounts.

old_man said:

The biggest problem with moving your shock mounts up that high is that with the same shock, it limits up travel. All in all, it limits your flex since you can only put so long a shock on due to the limited space.

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Yea I know that was goin on there. I was planning to run shorter shocks and probobly get similair travel with the shocks mounted towards the middle compared to a longer shock mounted on the outside of the axle. Different distances each point of the axle moves while articulating

or you could just cut into the floor, make or have someone make braces and mount, and call it done. shocks are out of the way and you don't limit your up travel

Super mud said:

Yea I know that was goin on there. I was planning to run shorter shocks and probobly get similair travel with the shocks mounted towards the middle compared to a longer shock mounted on the outside of the axle. Different distances each point of the axle moves while articulating

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As you tilt the top of the shocks inward, they become less effective. Not sure if it's a big difference but there is a difference.

if you notice that the factory staggers the shocks one in front of the axle. one behind. that is for handling and ride and stability.i have raised the lower shock mount points on one of my Cherokees and so has friends of mine. we have found no change in handling or ride or stability. we did how ever gain ground clearance.we also gain flexability because we already were running a shorter shock anyway.

jeeptec said:

if you notice that the factory staggers the shocks one in front of the axle. one behind. that is for handling and ride and stability.i have raised the lower shock mount points on one of my Cherokees and so has friends of mine. we have found no change in handling or ride or stability. we did how ever gain ground clearance.we also gain flexability because we already were running a shorter shock anyway.

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I thought xj's come with one shock in front and one in the rear to aid in preventing axle wrap?

I always wonder what the true reason behind the staggered shock mounts is, especially considering that the MJ runs them either both in front or both in back depending on which length bed you have. Granted it is also a SUA vs. a SOA design, but interesting nonetheless.

Super mud said:

I was wondering some about the rear lower shock mounts on the xj and what their placement has effect on the suspension. A while ago I did my 8.8 swap and welded my new tabs on as double shears up on the axle tube so they don't hang down and make the shock angle about vertical. Now that I thought about it more I noticed when I pulled the 8.8 it had this stupid looking 3rd shock than ran angled to the axle off the center section. I just relized it must have been for side to side movement with the leaf springs and wondered if the factory angle of the xj shocks has a similair effect and if would improve handling over my vertical placement setup. whats your ideas and opinions?

Click to expand...

I always figured the third shock was to combat axle wrap (by keeping the pinion from rising) but I could be wrong. Some exploders came with them and some didn't, the one I got my 4.10 geared 8.8 from had only the regular 2 shocks while a 3.55 geared 8.8 I pulled for a friend had the third shock. I haven't compared enough to know whether it's engine/gearing dependent, year dependent, trim level dependent, or what.

I thought the shocks on the XJ were on opposite sides because it gives the exhaust space to pass between the tank and the bumpstop on the passenger side and leaves space for the fuel filter and pump wiring on the driver side.

jeeperjohn said:

As you tilt the top of the shocks inward, they become less effective. Not sure if it's a big difference but there is a difference.

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This makes sense in my mind, but what's the reasoning behind something like the JKS crossover and the claim that the cantilever effect is better? Is such a setup intended for crawling because I can't imagine its good for go-fast.

snail said:

This makes sense in my mind, but what's the reasoning behind something like the JKS crossover and the claim that the cantilever effect is better? Is such a setup intended for crawling because I can't imagine its good for go-fast.

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The main reason for that mounting arrangement is to allow you to use a longer shock for more droop without worrying about bottoming out.

jeeperjohn said:

The main reason for that mounting arrangement is to allow you to use a longer shock for more droop without worrying about bottoming out.

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I know that, but what I'm trying to get at is the effectiveness of such a setup as the crossover versus say running longer shocks through the floor at a more vertical angle.

snail said:

I know that, but what I'm trying to get at is the effectiveness of such a setup as the crossover versus say running longer shocks through the floor at a more vertical angle.

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Every setup has pros and cons.

Crossover setup allows you to run longer shocks for more droop BUT lessens the effectiveness of the dampening which decreases stability and ride.

Shocks poking through the floor allow you to run longer shocks for more travel BUT......you now have holes in your floor and shocks sticking up in your cargo area.

pros and cons.

muddeprived said:

Shocks poking through the floor allow you to run longer shocks for more travel BUT......you now have holes in your floor and shocks sticking up in your cargo area.

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agreed. Though some simple dust boots fix one of those issues.

Okay, I was over-thinking it I guess

snail said:

This makes sense in my mind, but what's the reasoning behind something like the JKS crossover and the claim that the cantilever effect is better? Is such a setup intended for crawling because I can't imagine its good for go-fast.

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You know... I had to read their marketing on that a couple times.


This is what they say:
By relocating the upper mounting points toward the vehicle's center, the shock absorbers are positioned at an angle instead of vertically. A shock absorber mounted at an angle produces a cantilever effect that results in greater compression and extension when measured at the wheels. The reclined shock position also provides a mechanical advantage which improves ride comfort on shocks that would otherwise be too firm if installed in the vertical position.


They say it results in greater extension and compression when measured at the wheels... but so what? They don't say what the benefit of that is.

Then, they say you get a benefit if your shocks were already too firm. Which makes sense. As John said, angeling them inward reduces the effectiveness of the shock... so, it if is already too stiff, angeling them in helps... but if your shocks are fine, then angeling them inward will make them too soft.


I got this set up. My shocks were not too firm, and when I installed them, they were then too soft.