Hence the notion of 'just drive it for a week or two to let it settle' is nonsensical. Some guy installs them wrong, then when his rubber bushings deform over the next couple weeks he decides it was the springs settling.Ĭlick to expand.So while there is likely some range of physical stress you could subject a steel coil spring to that will cause plastic deformation, it should (on a quality spring) be well beyond the normal stress you would put on it in street driving. That'd be an interesting conversation to see.Īn install that doesn't set the bushing to neutral can cause those to deform over the next couple weeks post-install though, which is a surprisingly common install mistake and likely one of the reasons the 'springs take a while to settle' myth keeps getting passed around. If you're sure your engineering class is telling you otherwise I'd encourage you to contact Eibach and explain to them how their springs don't work the way they claim they do though. it simply doesn't happen (as per Eibach who made the springs being asked about by the OP and quoted from their own FAQ). which is what folks seem to think happens with springs taking a couple weeks to settle. I mean like after a couple miles of driving (or just letting it sit on the weight for a few minutes).Īfter that the suspension height shouldn't be changing further due to springs 'settling'. When you have the car in the air and don't have weight on the springs, then lower the car to put weight on them, you'll get a very small change. In short though a properly made coil spring should be elastic, and return to its original height, unless it's pushed beyond its limits (which it sure shouldn't be in anything resembling normal driving)

They even use a vehicle coil spring in one of their examples. Click to expand.Some more math on what it's doing here:

Mason spring isolators