I have recently purchased a 1986 w126 burgundy 300SDL and I’ve been fixing things over and over and I’m near towards the end of the list of things I need to get done to get it on the road. I’m trying to replace the rear springs and shocks. I already have the brand new springs, but I need the right specific thickness of rubber bushings to order so the car won’t be higher up than intended, which would prevent me from getting an alignment. Very confused, I’ve had a w123 before and loved it, I have sum experience with older Mercedes. But I have no idea which of website I should go onto to look up the different thicknesses. Or shop for them anybody have any ideas of sum websites or sources to find the right thickness?

I don't believe there is any way to predict which rubber spacer is going to get you a specific ride height.

If you were using genuine Mercedes springs and knew the part number, there may be something in the Mercedes W126 Chassis service manual that would give an approximate idea what spring goes with what rubber spacers.

You would get a better response if you changed your title to need help with W126 springs.

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84 300D, 82 Volvo 244Gl Diesel

This EPC page lists 3 different rear rubber buffers for the 1986 300SDL (W126.125).

1 burl - 9.5 mm (115-325-22-44-64).

2 burls - 14mm (115-325-23-44-64).

3 burls - 19mm (115-325-24-44-64).

Burls are the molded vertical protrusions on the outer lip of the rubber buffers (aka spring pads).

See what you have on your vehicle, and order them from your vendor of choice.
Best quality ones are the original OEM parts from MB. The forum sponsor carries them.

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

Why are you buying new spring pads? You may be very well served reusing the old ones. Are you sure the springs you’re buying have the right color paint combinations? That paint color defines the stiffness/coil diameter, and of course a not to spec/stiffer spring may rise higher, thereby requiring a thinner pad. But if the springs are right, it’s dubious to me that the pads are shot.

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Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (116k)
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1991 300D (228k)
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