I just installed them (Spidertrax 1.5") on my jeep. Sahara Unlimited with factory wheels/tires. The sole purpose was just for the look. I like the 18" stock wheels but didn't like how the wheels were tucked inside the fender flares. They look a lot different with the spacers installed. I will eventually replace the rubber with 33's. But i'm going to wait until I wear out the factory tires.