you would have be be pretty slammed like at least 3-4 inches for the lip to be scraping all the time id say. Even a 2 inch drop would be safe. Im lowered on Koni Yellows and Ksport GT springs thats 2.5F 2.25R and my mudflaps sometimes scrap but it has to be a huge hole or comming off a high curb or something. I dont think a lip kit will come that low.