Author Topic: Rear Suspension Removal  (Read 8916 times)

pauldridge

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Rear Suspension Removal
« on: March 26, 2009, 04:37:29 »
I'm hopefully removing my entire rear suspension this weekend.  Already have driveshaft removed, exhaust and fuel tank out, and all brake lines disconnected.  I've done extensive searching for the full procedure on this site, and have read the BBB...  I understand that I'll need some sort of spring compressor for the compensator spring, which I plan on fabricating.  However, from what I gather from previous posts, it may not be necessary to compress the main left and right springs prior to removal.

Am I missing something here?  I'd sure appreciate any guidance on the exact suspension removal process where current wisdom departs from the original procedure in the BBB?

mbzse

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Re: Rear Suspension Removal
« Reply #1 on: March 26, 2009, 08:12:09 »
I'm hopefully removing my entire rear suspension this weekend.../.. I'll need some sort of spring compressor for the compensator spring, which I plan on fabricating
This is a useful, self made compressor tool for the task of removing-mounting the transverse spring  (note: picture borrowed from waqas!)
Note also, this coil spring shown has 9 windings, and is for the Fintail Sedan W111. A W113 Pagoda is fitted with a spring that has 11 windings
A word of warning, do not allow the rear axle to fold too much (one side hang down free) when the shock absorbers, which regulate the movement, are detached.
this may (will) damage the internal sliding joint or other parts of the diffrential. Expensive!
/Hans in Sweden
« Last Edit: March 27, 2009, 10:59:36 by mbzse »
/Hans S

bpossel

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Re: Rear Suspension Removal
« Reply #2 on: March 26, 2009, 10:26:41 »
Phil,

In terms of removing the rear left & right springs...  with the car on jack stands, secure a standard hyd jack under the trailing arm.  Carefully remove the bolts on the front of the arm.  Then you can slowly release the jack pressure and lower the front of the arm and the spring will expand.  You can then remove the spring...  The tension on the left & right rear springs is no where near the tension on the front springs and the rear center spring.
Good luck and be careful!
Bob

waqas

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Re: Rear Suspension Removal
« Reply #3 on: March 26, 2009, 18:00:27 »
Hi Phil,
I wish I was back in Austin. I could lend you the exact tool pictured in Hans' post!  ;D  The picture is from when I removed my rear axle (along with all the junk in the background  :-[)

Bob has described it well, although placing a jack-stand under the rear axle is not really needed, and in fact can be a hindrance. In any case, once the spring pressure is relieved, that side of the car will need to be supported elsewhere.
  • I would let the shock-absorber remain connected, to keep the axle half from falling down.
  • Then, simply place your hydraulic jack under the trailing arm, near the front.
  • More importantly, I would support the car from the frame, just in front of the rear wheel-well.
  • Disconnect the little triangular mount plate (3 small nuts and 1 large nut).
  • Slowly lower the jack until the spring tension is relieved (the arm won't have travelled very far when this point is reached).
  • Take out the spring, and then you can support the axle and disconnect the shock absorber.
  • Once the two axle halves are hanging loose, this should relieve the compensating spring tension as far as possible.
  • Compress the compensating spring using the tool, and then remove the spring mount on the right).
  • You can keep the spring attached like that, whilst taking out the axle.
  • If you have enough headroom, you can actually remove the entire axle without removing the compensating spring.
« Last Edit: March 26, 2009, 19:03:12 by waqas »
Waqas (Wa-kaas) in Austin, Texas

tel76

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Re: Rear Suspension Removal
« Reply #4 on: March 29, 2009, 09:56:03 »
Hello Waqas,
I was very interested in your step by step rear suspension removal proceedure as i will be undertaking this on my project in the near future.
Would you please clarify two points,
  1-How did you support the axle when you removed the shock absorbers so as not to cause the damaged mentioned above by mbzse?
  2-How high must you raise the vehicle to remove the axle with the comp: spring in situ?
Eric

waqas

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Re: Rear Suspension Removal
« Reply #5 on: March 29, 2009, 12:48:19 »
  1-How did you support the axle when you removed the shock absorbers so as not to cause the damaged mentioned above by mbzse?

The damage can be caused if the axle is allowed to drop down hard (it can crack the diff casing).  If you lower it slowly, then there should be no problem. 

Regardless of whether or not you plan to remove the rear axle with the comp. spring attached, you will probably need some kind of rear axle support, in addition to a transmission jack (or the like). There are commercially available axle supports (attached to your transmission jack), that supports the axle tubes as well. This is best.

However, each time that I've done this, I've simply used a home-built wooden contraption that sits on my hydraulic jack and spans across the entire axle to support everything. This allowed me to wheel out the axle whilst still attached to the jack, once I lowered it. (without accumulating yet another specialized tool!)

If you plan to remove the comp. spring, I would disconnect the shocks and the diff. mount (in the trunk) absolutely last:
  • Remove all the springs, disconnect lateral support rod, disconnect driveshaft, etc.
  • Raise both axles until they match the profile of whatever axle-support/jack setup you're using.
  • Place your axle-support/jack under the diff and axles until everything is securely supported.
  • Finally, disconnect the shocks and diff mount in trunk, and then lower the axle and wheel out.

If you do not plan to remove the comp. spring:
  • Remove the two suspension springs, disconnect lateral support rod, disconnect driveshaft, etc.
  • Place hydraulic jack underneath axle half (near the trailing arm support).
  • Disconnect shock, and then slowly lower until it reaches the stop (do not allow it to simply drop).
  • Your axle-support/jack will look very different due to the "upside down V-shape" of the axle.
  • Place your axle-support/jack under the diff and axles until everything is securely supported.
  • Disconnect diff mount in trunk, lower the axle and wheel out.

  2-How high must you raise the vehicle to remove the axle with the comp: spring in situ?

Good question. I've done this with comp. spring attached only once, and I don't quite remember. I do remember that my craftsman jack-stands (the big yellow ones) were about sufficient to give me that height. However, even though I'd already removed the fuel tank, I still needed to extract the axle through the side (wheel well opening) due to the height constraints. My feeling at the time was that this type of extraction is best served by a shop lift supporting the car.

It must be noted that if at any point (before disconnecting the diff trunk mount) you feel that the clearance is insufficient, you can always lift up the rear end underneath the differential, and raise your chassis supports from the rear.

If you ask me, I would remove the comp. spring. If you plan to do anything on the rear axle whilst it is out (replace rubber parts, clean/paint, etc), I would feel much more comfortable working without having a loaded spring so close by. But I can be over-cautious at times. So, do what makes you feel comfortable.
« Last Edit: March 29, 2009, 12:53:19 by waqas »
Waqas (Wa-kaas) in Austin, Texas

DavidBrough

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Re: Rear Suspension Removal
« Reply #6 on: March 29, 2009, 16:45:52 »
Hi Eric,

When I changed my axle I just used stands and was able to remove everything under the fuel tank. I removed the comp spring completely and fixed a piece of wood in its place to hold the tubes straight and two jacks easily pulled it out. These two pictures may help. If you leave the spring on you will need to raise the car a bit higher or pull the axel out sideways through the wheel arch.

ja17

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Re: Rear Suspension Removal
« Reply #7 on: March 29, 2009, 19:04:14 »
Hello,

If you are from northern salty climates, make sure you find a good solid chassis area to support the car in the rear.  Lots of these old cars have rust weakened areas.  When the rear axle is beiing removed it is an issue to find a good solid place to support the car, depending on the condition of your car's chassis.

Using a nice strong four by four section of lumber spanning the entire width of the car just in front of the trailing arms works nicely on rusty chassis. The  four by four is supported by supports which are under the car.  Additional wooden blocks can be added above the four by four tp support the chassis in solid areas. You are actually building a bridge for the bottom of the car to rest on during removal of the diff.

Car ramps, wheels, jack stands, and wood blocks  can be used to support the ends of the "bridge".  Be safe, always have a backup. I always slide the wheels under the car when working on jack stands, just in case something slips. I always keep a nice neat stack of short cut four by fours around for blocking.
« Last Edit: March 29, 2009, 19:06:08 by ja17 »
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