FWIW, I'm about to undertake a similar lowering operation on my 300TD. Before the transmission conversion, the wagon was easily an inch higher than the sedan and after removing +275# of auto tranny from her gut, she now sits a good 2" higher than my 300D.

I don't mind the height so much but I think that the front end's spring rate is much too stiff. Consequently, I'm going to try out a set of front springs from my 240D parts car. They are 10mm longer than the 300TD springs but, the rate is softer. I don't have the exact numbers in front of me but I think that the wagon's springs compress as something like 20 mm/1000 N and the springs from the 240 compress at 23.3 mm/1000 N.

Hopefully, that rate won't be too soft for the weight of the bigger engine.

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Never a dull moment at Berry Hill Farm.