In addition to Neil, get in touch with Farrukh Majid-he's done as much or more fiddling with the spring/shock setups on later W124s (Neil's car is an earlier W124, which had different springs & struts to begin with) than even Neil. Currently, I think Farrukh settled on 500E front springs & struts, as well as 500E springs at the rear. Remember, a 500E has self-leveling too, and weighs just a bit more than the wagon. If you go all the way into an MBZ Sportline or Bilstein Sport setup, ride quality will be severely compromised.

That said, if I were you I'd first look to replace my rear air cells, then see how it rides. If still too soft, I'd do 500E springs & shocks in the front as a next step.

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"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo