Is my shock blown?

DaveC

DaveC

TJ Addict
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Jan 3, 2019
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Gilbert, Arizona
Recently noticed the TJ seemed to be squatting toward the right rear. Tonight I measured (no rear seat, no gear, totally unloaded in the back, sitting on level ground) and sure enough, the right rear shock is 1/2 inch or so shorter than the left rear. I haven't noticed any difference in ride. The lower shock mount is a touch wet, and the fluid isn't water, so I'm assuming I have a small seep/leak in the shop (no major signs running down the shock, but I did drive thru water recently, which could have washed any small/fresh signs off). The shocks have 20k miles on them and in any other vehicle, the shocks have lasted 80-100k miles and it was noticeable when they needed to be replaced.

  1. Does it sound like my shock is blown or on its way to being blown?
  2. Is this the normal amount of life I should expect on shocks for a TJ that's not abused, but is 'well used' (moderate to difficult trails)?
 
macleanflood said:
More likely springs or something in the suspension. Shocks dampen and rebound motion...they don't necessarily set ride height.

-Mac
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Makes sense. Springs are same age as shocks, so I wouldn't think sagging should be expected afyer 20k miles. No work done in that area since installed.

If the spring were unseated briefly, would that possibly cause it to reseat incorrectly and thus cause the shock to be compressed that little bit?

Sorry, may be a dumb question, but I'm mostly a novice trying to figure this out. 😁
 
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Rickyd said:
Engine torque makes our tj's squat in the right rear first,springs or just a spacer are the fix. If you think you might have a blown shock then unbolt one end of it and see how it acts when you move it through its range by hand
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Got it. Pushing the bumper up and down, it seems like it may a tiny bit softer than the other side... but the difference is so minute, I can't be sure it's not just me expecting it to be softer.
 
With the shock right next to the exhaust i wonder if heat can cook them. My tj had a dead right rear shock when i bought it
 
DaveC said:
Got it. Pushing the bumper up and down, it seems like it may a tiny bit softer than the other side... but the difference is so minute, I can't be sure it's not just me expecting it to be softer.
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Super common for the right rear to be lower than the left rear.

Any difference of shock stiffness can’t be gauged by manipulating the shock while it’s on the rig. The rig literally weighs over 1,000 pounds on that corner. Remove the springs and they’d totally compress under the weight.
 
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As said above, it's not your shock causing the rear passenger side corner to sag which also as said above, is very common. The shock doesn't support the weight, that's the sole job of the spring. I'd do nothing but replace the spring or add a small 1/2" to 1" spacer to the top of the spring. My r-r corner sagged a full inch.
 
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Jerry Bransford said:
As said above, it's not your shock causing the rear passenger side corner to sag which also as said above, is very common. The shock doesn't support the weight, that's the sole job of the spring. I'd do nothing but replace the spring or add a small 1/2" to 1" spacer to the top of the spring. My r-r corner sagged a full inch.
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It's actually a thing even on the newer Jeeps. The factory springs (and aftermarket too) on my Gladiator are about 3/4 inch taller on the passenger side... now, that's partially to compensate for the fuel tank living on the passenger side, but they do still sag at the right rear after a lot of miles.
 
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Artsifrtsi said:
It's actually a thing even on the newer Jeeps. The factory springs (and aftermarket too) on my Gladiator are about 3/4 inch taller on the passenger side... now, that's partially to compensate for the fuel tank living on the passenger side, but they do still sag at the right rear after a lot of miles.
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On the TJ it's caused by engine torque spiraling rearward where it ends up at the right corner.
 
Artsifrtsi said:
It's actually a thing even on the newer Jeeps. The factory springs (and aftermarket too) on my Gladiator are about 3/4 inch taller on the passenger side... now, that's partially to compensate for the fuel tank living on the passenger side, but they do still sag at the right rear after a lot of miles.
Click to expand...

OME has side specific springs for our TJ’s. For example, the 2933 and 2942 labeled A and B. What I’ve read was this was to compensate for the drivers weight, but I really don’t know.

I’m also not convinced the rear passenger corner sags due to rotational engine torque. I’m experientially aware of the front driver corner raising and the rear passenger compensating by lowering a bit, but I’m not convinced that slight, momentary compensation is sufficient to cause it to sag.
 
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Jerry Bransford said:
On the TJ it's caused by engine torque spiraling rearward where it ends up at the right corner.
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Yep, motors in the newer Jeeps still spin the same direction and the torque still loads the right rear, just like in the TJ. But compounded by the weight of the fuel tanks.
 
JMT said:
I’m also not convinced the rear passenger corner sags due to rotational engine torque. I’m experientially aware of the front driver corner raising and the rear passenger compensating by lowering a bit, but I’m not convinced that slight, momentary compensation is sufficient to cause it to sag.
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I just went outside and measured my rear flare/tire clearance, after nearly 7 years with the same springs. I have 7.5" on both sides (within 1/8") for the pavement not being perfectly level. I guess my Jeep just doesn't have enough torque to cause the "Gansta Lean". :unsure:
 
JMT said:
OME has side specific springs for our TJ’s. For example, the 2933 and 2942 labeled A and B. What I’ve read was this was to compensate for the drivers weight, but I really don’t know.

I’m also not convinced the rear passenger corner sags due to rotational engine torque. I’m experientially aware of the front driver corner raising and the rear passenger compensating by lowering a bit, but I’m not convinced that slight, momentary compensation is sufficient to cause it to sag.
Click to expand...

These are actually OME springs (and shocks), so maybe if I gain a few lbs to get back to my college football playing weight, I can even it out. :LOL:
 
Thanks to everyone for the replies and info. Sounds like I'll just need to toss in a spacer at some point to level it back out. (y)
 
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