On both of our SD's we opted to just shell it out and have all three replaced. I got new OEM springs, the second thickest spring pad (dealer recommended it) which is 14mm....and new Bilstein HD shocks. I think the rear of my car was raised about 4+ inches after. Big difference. Also the new springs and HD shocks make it able to carry more without having it sag to the ground....aka....a few people in back and stuff in trunk....or heavy load on our utility trailer hitched up to the car.

Well worth it....looks so much better and rides better too.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)