The Monroe Reflex light truck Monotube shock absorber 91501 really firmed up the ride on my 2004 Silverado 4x4 the shocks also gave the front end a little lift about a inch. Installation was a breeze the hardest part is getting the top nut off the shock, I started using WD40 weeks before and also ran a nut down the rusted treads to help break up the rust. While the instructions call for installation with tires on the ground you will have to raise the truck up in order to install the shocks.