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DIY - W210 Rear Subframe bush replacement

Discussion in 'DIY: Suspension, Steering & Brakes' started by brandwooddixon, Jul 31, 2010.

  1. brandwooddixon

    brandwooddixon Senior Member

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    As time passes by you may notice that your beloved no longer handles quite the way that she used to . She may feel a little wayward in a straight line, lurches around corners and jumps sideways when surprised by bumps on bends.

    In all she's not quite so composed with her rear end as she used to be.

    It's very likely that she needs a bush replacement or two.

    In this scenario, rear subframe bushes are a general culprit that is often overlooked. It can take a very close inspection to determine whether they are worn or not. Certainly, unless you have a lift, you'll need to jack up the car and remove the roadwheel to get any idea of how badly they need replacing.

    You can replace all four bushes if you wish, but its generally the front pair that need replacing. The rear pair are twice the size.
    Here I only replace the front pair, but I would imagine that the sequence is much the same apart from the bushes being fitted from underneath the subframe, where as the front pair are fitted from above the subframe and are thus easier to remove if you don't have the special tool.

    Here's a diagram showing the relation of the bushes to the subframe and where they are fitted.

    subframe drawing.jpg

    Here's a picture of a new front bush for the rear subframe along with its safety washer and retaining bolt.
    New bush smaller.jpg

    Tools needed:
    Torque wrench (110Nm minimum capacity)
    Socket wrench with 6" extension.
    E-14 Torx socket.
    Silicone lubricant (spray or "grease").
    A jack (preferably a trolley jack).
    At least two axle stands.
    A cold chisel or similar.
    A small crowbar or similar.
    Thread lock (if not replacing the bolts for the rear bushes).
    Some wooden or steel packing pieces of at least an inch thickness.


    A general warning:

    As with all operations involving the lifting of a vehicle do not rely soley on a jack to support it. Always use a suitable support (axle stand) once the vehicle has been lifted.

    Not only will you need to support the vehicle, but you will also need to support the subframe or a suitable part of the rear suspension. Once the bush bolts have been removed the road spring will force the subframe down away from the car body and as the subframe supports not only the rear suspension but also the differential it all weighs a tidy sum.

    It is for this reason that work should be performed on one side at a time. On no account release all four bolts or both bolts to the front bushes or both bolts to the rear bushes at the same time. Serious injury may result if the subframe is not supported, as you could be trapped underneath it.

    Saying that if you're mindful of these facts then there's nothing to stop you from having a go yourself at changing the bushes.

    Stage 1:
    The day before, place your new bushes into the deep freezer and leave to cool. Pop them in a bag first so as not to annoy she who must be obeyed.

    Stage 2:
    The next day.
    Chock a front wheel - both in front and behind it.
    On the opposite side of the car loosen the wheel bolts before jacking the rear up and removing the road wheel.
    You'll now need to place an axle stand under the rear suspension. I found that it was easier to place it at one end of the lower suspension arm where it attaches to the subframe. My car has a plastic cover over the bottom of this arm, it is clipped on and held by two 8mm bolts. I removed this first. Note that at this point you only need to raise the car body enough to remove the road wheel and then get a support under the suspension arm.
    Here's a picture showing the point I chose to place the axle stand to support the subframe.
    support arm hinge.JPG

    Once you have done this you can remove the two subframe retaining bolts on that side of the car. One in the front bush and one in the rear bush. They have Torx heads and require an E14 socket and the 6" extension if I remember rightly. If there's any tension in the bush then they'll release with a bang as the roadspring forces the subframe down.

    Once the bolts have been removed jack the car up further until the bushes are clear of the chassis fixing point by several inches. You'll need to fit the new bush, so leave some space. Be careful not to stretch the brake pipes, ABS and brake wear wiring.

    Here's a picture that shows what it looks like at this stage.
    General view subframe bushes.JPG

    And here's a closeup of the first bush to be replaced. It may not look too bad, but if you look very closely you may see that the metal centre section that holds the rubber section of the bush to the car chassis is no longer attached to the rubber. I was able to push it a good inch or so up, out of the bush with my fingers!
    Old front bush closeup.JPG


    Stage 3:
    It's now just a case of brute force and ignorance. Give that bush a good bashing!
    Actually, there are four tabs around the top that can be prised up. You can see them in the picture of the new bush.
    You can the rip the inner section of the bush (if you have enough leverage) up and out of its casing. Place the jemmy into the top of the metal core and lever away! I pounded away for an hour with a cold chisel and lump hammer the first time, before I found that trick. Be prepared for it to take a good while though.

    I wouldn't recommend burning the bushes out due to the close proximity of the fuel tank and lines; brake pipes; ABS sensor wiring and underseal; all of which will catch fire in a nice but disasterous way.
    The bushes are also oil filled. If like mine the oil will have leaked out long ago, but they are still hefty pieces of rubber and will take a long time to burn out.

    Once you have the main body of the bush removed you'll still need to make sure that you've removed the outer section. This is best done by hammering it with a cold chisel so that it collapses in towards the centre. Then prise it out and give the socket a good clean. Try and avoid damaging the subframe fitting hole itself.
    This may take a while to do.

    Stage 4:
    Now when you're ready fetch the new bush from the freezer, give it a good coating of lubricant and with the flat edge facing towards the front of the car stick it in the hole.

    You can't fit the bush by applying any pressure to the centre section as this will just damage it. Pressure must be applied to the outer edges. I placed some steel bar that I have lying around and some wood either side of the centre "post" and then with an axle stand under that part of the subframe I lowered the car onto it.

    As you lower the car make sure that the rear bush fits up to its chassis mount as well. Watch those fingers as you do so.

    By doing this I managed to press it most of the way in, but I did resort to raising the car slighty so that I could replace the packing with a crowbar and got jiggy with it. In the end it was only proud by 1/16" so I wasn't that bothered about getting it flush, just so long as both sides matched. I also left it with weight in the boot and got a cuppa.

    Fit the retaining bolts. Apply thread lock to the rear bolt if not renewing and fit the safety washer to the front bolt concave side down, rubber side up.

    Tighten both bolts to 90Nm.

    Replace the suspension arm cover, remove the axle stand from under the subframe (a moment of truth!), replace the road wheel, lower the car and your done.
    Tighten those wheel bolts to 110Nm.

    Then remove the wheel chocks and place on the front wheel before repeaing this on the other side of the car.

    In all I would think that it took around 5-6 hours to do but once done you'll be amazed at the envious glances that you get from people as you glide around in luxury. :)
     
  2. television

    television Always remembered RIP

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    Ask a mod to move it to the DIY
     
  3. Naraic

    Naraic Moderator

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    Great write up, and surely a sticky. When taking out the E14 torx bolts, did you find them difficult or straightforward?
     
  4. kth286

    kth286 Senior Member

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    did the exhaust not get in the way on that side ? Lowered it ?

    would it have been useful to disconnect the anti roll bar link ?
     
  5. rapide

    rapide Senior Member

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    bushes!

    great write up by brandwood! looks like a 210 with the amount of ferrous oxide on every weld / seam etc, could be mine! and thats just the back end! Oh well!
     
  6. Naraic

    Naraic Moderator

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    Yep, as the title says, a 210.:)
     
  7. OP
    brandwooddixon

    brandwooddixon Senior Member

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    No they weren't too bad to remove. The 6" extension was necessary due to the position of the subframe. A long bar may help to get them started.

    The exhaust runs down the other side on my car and didn't really get in the way, whereas you need to be careful of the ABS and brake wear sensor wiring and brake piping. You're only dropping the subframe by a few inches so it wasn't a problem.
     
  8. OP
    brandwooddixon

    brandwooddixon Senior Member

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    Yep.

    Whilst I was working under there I also removed the wheel arch liners (4 plastic bolts) and made ready with some rust treatment and prevention - POR-15, underseal and waxoil.
     
  9. Frontstep

    Frontstep Senior Member

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    Excellent thank you for your time and effort in producing this.
     
  10. Naraic

    Naraic Moderator

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    Edited.....
     
    Last edited: Jul 31, 2010
  11. dieselman

    dieselman Senior Member

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    The bushes can normally be pressed in with water pump pliers or similar clamps
     
  12. Dunhamkid

    Dunhamkid Senior Member

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    How much do the bushes cost?
     
  13. Naraic

    Naraic Moderator

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    About £50 for the front pair, a little less or the rear ones. Check out Eurocarparts.
     
  14. Kompressor

    Kompressor Senior Member

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    Good DIY thread. Thanks for your effort and for sharing. Much appreciated and kind of you to take the time to write it all up. Good luck getting the mods to make it a DIY sticky though.
     
  15. OP
    brandwooddixon

    brandwooddixon Senior Member

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    I did post Blobcat a message.
    Not sure who else to pm though.
     

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