How do i check the U- joints on my 1993 jeep grand cherokee larado?

Answer 1

Usually the driveshaft U joints make a noise of some kind, or they go "clunk", "klang" when you shift the transmission into drive or reverse. They're easy to replace, but mark the driveshaft so you don't get it 180 degrees out of phase and cause a shake in your car when you reinstall it.

DIY U joint replacement in a driveshaft:

While clunking, rattling and a rumbling vibration at speed are telltale signs of worn U-joints, there is no way to tell if a U-joint is worn by looking at it from the outside. Removing the driveline and moving the U-joints by hand can reveal crunchy movement or impending failure, but the only way to be sure that it's in tip-top shape is to replace the U-joints. Since most U-joints come from the factory full of grease, once they're done—they're done. Some replacement U-joints have grease fittings for service while others, like the OEM units, are lubed for life. Replacing U-joints is a relatively easy affair once the driveshaft is out of the vehicle.

http://www.extremehowto.com/xh/article.asp?article_id=60402

Answer 2

Ok. Put it in drive. Hold the brake pedal very firmly. Shift to reverse. If you hear or feel a noise then you should suspect bad U-joint. If no noise or clunk should be good.

Do this in both 4-wheel and 2-wheel drive so you check front and back U-joints. .

Answer 3

Which ones? Theres a ton of U joints in automobile construction. Just the steering shaft alone can have half a dozen...

The main ones though, shouldnt be too hard.

Here's a site that has a really vague summary :) For replacing them, the guy above tells how to check 'em.

http://autorepair.about.com/cs/doityourself/a/aa102602a.htm

Answer 4

crawl under your jeep with it in park and the parking brake firmly applied. running down the center of the jeep underneath is the drive shaft. reach up and try to twist the drive shaft with your hands. if it moves at all in either direction you have bad u-joints and they should be replaced asap.

Answer 5

well, one thing you'll notice that would be a sign of it being bad is excessive noise and vibration, a visual inspection will show grinded and/or chipped ends on the driveshaft.

Basically just look for any wear or damage.