Originally Posted by JP_335xi
If a dealer tries that bull shit, try a different one
BMW would absolutely have the right to affect your warranty with regards to other suspension components or any other affect the non OEM springs have on the car.
example: suppose after you install the stiffer springs, your dashboard starts to rattle (very common with stiffer suspension) - why would they be responsible? Lowering the car will put more stress on the stock shocks, links, sway bars etc. If any of those parts ever fail (unlikely) after installing stiffening springs, you better believe BMW will not repair them under warranty. That said, I wouldn't worry about it as the odds of any of those failures with the exception of developing rattle noises is pretty small.