My commiserations. I too suffer from back problems, plus I'm 6"4". As I mentioned in my earlier post, I find the seats comfortable. Lately, I found that a simple change in the way I sit in a car has helped me tremendously. I now sit more erect -- the seat back is considerably less reclined. Though I haven't driven my E320 cross country, I do in another car (01 Sable) and even with an ongoing back problem I have no discomfort when the seat back is erect.

Though your mechanic pointed out the play in the throttle linkages, did he offer to adjust them? The bowden-design cable is adjustable and this adjustment does affect the way thte transmission shifts. Perhaps a proper adjustment would solve the sluggishness you experience with your car.

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95 E320 Cabriolet, 169K