Rear Shock Replacement?

Discussion in 'Street Suspension' started by Josh D, Jan 13, 2020.

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  1. Josh D

    Josh D TYF Newbie

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    Hi guys,

    I bought a 2016 GMC Yukon XL Denali and looks like the rear shocks are already starting to leak. I am new to Magnetic Ride shocks, but can't figure out why the shock looks to be leaking in the air bag portion of the shock.

    Can someone chime in and let me know if this is the shocks leaking or something else related to the air bags?

    I noticed that issues can involve the air compressor and wondered if maybe it could be related as well.

    Thanks in advance for all of the help!

    Left Shock 1.jpg Left Shock.jpg Right Shock.jpg
     
  2. jonnytahoe

    jonnytahoe Full Access Member

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    Looks like a Leak.
     
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  3. Big Mama

    Big Mama Full Access Member

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    Looks like the shock seal is leaking. How often do you hear the compressor running? Is there anything else around the shock wet? @iamdub has a bit of experience with these too.
     
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  4. Dcmaynor

    Dcmaynor Full Access Member

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    @RockAuto has what you need. Usually has a discount code here as well. Lifetime warranty for my replacement that took 39 minutes to swap out.
     
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  5. iamdub

    iamdub Hold on... Lemme overthink this for a bit...

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    It looks like an oil and it looks like it's coming from the shock since there's nothing else around there that would wet it just in those areas. I'm thinking that odd, sharply-defined sloped part at the top of the shock in two of the pics is a shadow that's screwing with us.

    Yes, the compressors eventually fail, but what usually happens is the bellow on the shock wears and develops a leak. The leak makes the compressor run longer and more often than usual, so its already aged life is accelerated and it tends to fail soon after cuz nobody really notices the shocks leaking.
     
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  6. Josh D

    Josh D TYF Newbie

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    So is the fluid leaking out of the top of the shock and when the air bag inflates, the fluid is being pushed out of areas that are leaking air? I squeezed each air bag and it seems there's a little air in them, but I can easily push in on the air bags. I have heard the compressor kick on a few times, but doesn't seem like it stays on for very long before turning off.

    It's going back to the dealer in a few weeks for some other repairs as part of the purchase and they are supposed to look at the shocks. Just concerned they are going to kick the can down the road, tell me this is normal so they don't have to eat the repair and will become my problem later.
     
  7. Dcmaynor

    Dcmaynor Full Access Member

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    Neither fluid not air should leak out of the shock. Either one requires a shock replacement.
     
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  8. iamdub

    iamdub Hold on... Lemme overthink this for a bit...

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    It's probably not leaking air... yet. The air bellow is a sleeve bag that rolls over the shock body as the suspension cycles. Picture the bellow as a doghnut, but tall and with a shock passing through the center hole. Shocks start leaking from the seal where the rod slides in and out. Since the shock rod is inside the center of the "doughnut", the leaked oil will collect in there and will seep out whenever and wherever possible. It looks like it's seeping out lower down the shock body and getting smeared up and down the body as the shock and bellow is compressed and extended.

    When parked, the bellows will only have about 5 psi in them. A few seconds after cranking the engine, the system will run the compressor for about 5 seconds as a self-check and to put a minimum amount of air in the bellows so they hold their shape while driving. If the vehicle is loaded down, the compressor will run to fill the bags more to lift the vehicle until the sensors indicate the vehicle is at its preset height.
     
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  9. Josh D

    Josh D TYF Newbie

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    Thank you so much for that explanation. Now I understand what's going on. Should I press the dealer to get these replaced, or are they really fine till they either start dripping on the floor or totally cease up? I have read on other forums that can be the lip service from service advisors when trying to get shocks replaced.
     
  10. Sangster

    Sangster Member

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    Those 100% appear to be leaking. I would press for them to replace them.
     
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