Universal joints allow drive shafts to move up and down with the suspension while the shaft is definitely moving so power could be transmitted when the travel shaft isn’t in a directly line between your transmission and drive wheels.
Rear-wheel-drive vehicles include universal joints (or U-joints) at both ends of the drive shaft. U-joints hook up to yokes that likewise allow drive shafts to go fore and aft as automobiles go over bumps or dips in the street, which successfully shortens or lengthens the shaft.
Front-drive vehicles also employ two joints, called frequent velocity (or CV) joints, nevertheless they are a distinct kind that also compensate for steering improvements.
On rear-drive vehicles, one indication of a put on U-join is a “clank” sound whenever a drive gear is engaged. On front-drive cars, CV joints typically make a clicking sound when they’re donned. CV joints are included in protective rubber footwear, and if the shoes or boots crack or are usually ruined, the CV joints will eventually lose their lubrication and be broken by dirt and wetness.
A U Joint U-joint is found in both front wheel drive and rear wheel travel cars. Although they are different in design, they possess the same purpose of giving the drive 
educate some flexibility. That is required as all vehicles flex while in movement.
U-joints are located on each of the ends of the trunk travel shaft, whereas CV-joints are found on front wheel travel cars. Each allows the drive shaft to rotate as the differential techniques in relation to the rest of drive train attached on the chassis.
The U-joint functions to save lots of wear and tear on your own vehicle’s transmission. Failing to possess a universal joint alternative done when necessary 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 include: