sounds to me like you may have the wrong spring, or at least not the ones you desire. Although MB OE ride heights are ridiculously high, any spring that advertises a 40mm reduction in ride height and doesn't give very much...well, that just don't add up. You may have a spring setfor your chassis, but perhaps you have a 4 cyl spring set for a 6, a 6 for an 8 cyl...just because it fits doesn't necessarily mean it works. The weight differences can oftentimes make quite a difference. Most of the quality name brands, when used with the short pads, are really low. Plenty low enough for proper street looks and ride. If you've got the right parts, and want it much lower than that, you're out of my realm. That's not usable or safe for anything. Hope this helps.