The truck was sitting on the side of the road. No one was around; whoever owned the truck had left some time ago – possibly days ago. The problem was obvious. It dangled there underneath the truck – a shaft of steel with one end resting on the ground.

The driveshaft had fallen out of the back of the transmission. But why?

Looking a little closer, you notice that this isn’t an everyday pickup truck; this is one of those modified pickup trucks. It has great big, chrome pipes extending out from below the rear bumper. It has one of those vehicle wraps – an awesome and modern design that really sets it apart. And, most importantly, it has a great, big set of tires.

Those over-sized tires fit under the truck because it also has big, visible springs and shocks. In other words, the truck has a lift kit. It looks cool but it’s also functional if someone wants to take it offroad. The problem is that the driveshaft has fallen out of the back of the transmission, which brings us back to the question of ‘Why?’

The answer is probably fairly simple; when someone installed a lift kit to raise the truck they didn’t stop to consider the effect this would have on the space between the truck’s transmission and the rear axle. As the truck moves up, the position of the transmission remains consistent with the position of the truck’s chassis. But, the rear axle, in particular, the hub, moves away from the chassis.

In the process, the distance from the spline on the back of the transmission, and the U-joint at the rear axle, grows. The driveshaft has to extend to fit that increasing distance. A modification is required.

Someone who installs a lift kit on their own truck, in their own backyard, may not recognize the laws of physics that require modifications to the driveshaft. This is probably the person whose truck is stuck on the side of the road now.

The truth is that, installing a lift kit, such as a Superlift Suspension, or an Airlift Universal Air Spring Kit, is actually a fairly complex job. Installed correctly, it can turn that everyday pickup into a virtual monster-truck of your dreams. Installed incorrectly, that dream can turn into a nightmare.