A u-joint is a joint placed in a rod that allows the rod to bend in any direction at the location of the joint. The drives shaft of most motorized vehicles consists of two u-joints, though they've been around quite a bit longer than cars and trucks. The idea behind universal joint hardware came from the old gimbals that the Greeks used in devices such as the ballistae.

While it may sound complicated, the idea behind a u-joint is simple. Take two ordinary hinges, put them at 90� angels to each other and assemble the rod. If you're working with u-joints, remember the following:

1. U-joint replacement is a simple procedure

2. If there is any kind of vibration in equipment that requires a u-joint, check that one of them hasn't frozen

3. There are many applications for u-joints in industry

Action Steps
The best contacts and resources to help you get it done

Purchase universal joints for industry and keep your equipment running smoothly

Industrial u-joints meet special needs within the scope of whatever industry they are a part of. Some rotate mixers, others maybe used to keep large gears turning smoothly. Whatever the use, they will eventually wear out and need replacement.

I recommend: Lovejoy offers a large selection of u-joints for sale that meet various spec requirements. If you're looking to buy universal joint hardware for cars, be sure to click over to Direct Industry and look at their selection.

Make sure the u-joints on your vehicle keep turning smoothly

Universal joint replacement is a common repair on most vehicles because they tend to wear out, even the most well made vehicle. Before making any online purchase of a u-joint, be sure you have all the information about your vehicle. Taking apart the driveshaft only to learn that you have the wrong piece of hardware can be frustrating.

I recommend: For a wide range of vehicular u-joints, visit D & M Auto Parts Corporation. They have a wide selection of universal joints that will fit most vehicles. Parts Train offers another excellent u-joint distributor and offers a selection of quality parts for various makes and models of vehicles.

Find the right kit to repair the u-joints in your life

If you have the tools and the know-how, u-joint repair is a simple task. As with any repair, it's important to have the right equipment and the right parts.

I recommend: For a u-joint repair kit, visit Li Qun Auto Parts Manufacturing. They have an entire kit dedicated to the repair and replacement of u-joints on multiple vehicles. RestockIt.com also has a u-joint repair kit that may suit your needs.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  A single u-joint in a rod will create vibrations. Adding a second universal joint to the rod will create a smooth, even rotation.