Universal joints allow travel shafts to move along with the suspension as the shaft is usually moving so power could be transmitted when the drive shaft isn’t in a direct line between your transmission and drive wheels.
Rear-wheel-drive vehicles possess universal joints (or U-joints) at both ends of the drive shaft. U-joints hook up to yokes that also allow drive shafts to go fore and aft as automobiles review bumps or dips in the road, which effectively shortens or lengthens the shaft.
Front-drive vehicles also make use of two joints, called regular velocity (or CV) joints, but they are a numerous kind that also compensate for steering improvements.
On rear-travel vehicles, one sign of a worn U-join is a “clank” sound whenever a drive gear is engaged. On 
front-drive automobiles, CV joints typically make a clicking noises when they’re worn. CV joints are covered by protective rubber boot styles, and if the boot styles crack or are in any other case damaged, the CV joints will eventually lose their lubrication and be destroyed by dirt and moisture.
A U-joint is found in both front wheel travel and rear wheel travel cars. Although they will vary in design, they have the same purpose of giving the drive teach some flexibility. This is required as all cars and trucks flex while in action.
U-joints are found on each one of the ends of the trunk travel shaft, whereas CV-joints are located on front wheel travel vehicles. Each allows the travel shaft to rotate as the differential U Joint movements in relation to the rest of drive train installed on the chassis.
The U-joint functions to save wear and tear on your vehicle’s transmission. Failing to have a universal joint substitute done when needed can cause substantial damage to your vehicle in the future.
There are a few warning signs that U-joint or CV-joint is failing. They consist of: