My U Joints are shot!!!

[CoastieCosta567]

Thanx Etl..

[tomdietrying]

My U-joints went bad around 90,000 miles. Basically, the U-joint connects to the drive shaft. Your drive shaft should be tight and steady. If you grab your drive shaft with two hands. Try moving it back and forth. It shouldn't move at all. If it does, your U-joint needs to be replaced.

Also, if the back of your car shakes in the rear suspect the U-joint. Go 20-30 miles per hour, the car starts shaking, release your foot off of the gas, it should ease shaking. If this happens, you have bad U-joints.

Peace.
Tom
012009

[tom4bren]

taylorRichie,

Unless I'm mistaken (it happens) the Universal Joint is actually comprised of the plus shaped piece (forget what the real name of that piece is), the yoke (actually 2) and the spline. Typically tho, you only need to replace the plus shaped piece - there are roller bearings inside the end caps & those are usually the only thing that goes bad.

The good news is that the parts are usually cheap. The bad news is that it can be a real pain to replace them. If you do it yourself, make sure you put them back together EXACTLY the same as they came out. If you get the phase wrong, you'll get UBER vibration.

Did a little research:

The piece shaped like a plus sign is called 'the cross'

Also: "Among the most common causes of U-joint and slip failure is the lack of proper lubrication. Properly sized U-joints that are adequately lubricated at recommended intervals will normally meet or exceed operational requirements. Proper lubrication flushes of U-joints thus remove contaminants from the bearing caps."

[taylorRichie]

Very good Tom

Thanks for the correction.

The Universal Joint is the combination of the Yokes, The Cross, and the parts that keep 'em together.

I greased my U joints this evening, but I could get much to even penetrate the zerk... weird.

Awesome Image of the complete U-Joint

[taylorRichie]

Back when I used to run parts (when I was 17, so 10 years ago) I used to go here:
http://www.sixstates.com

For all of our driveline components.

If you removed your U-Joints, and brought them in I bet they could match them up and possibly upgrade you to better units.

Just a thought for those in need.

[etlsport]

sorry, no video tonight.. got called into work.. should have it up over the weekend

my joints took a little muscle to force the grease through... if you are having grease come back out of the zerk fitting, it either means your fitting is jammed up with a small pebble or your grease gun tip is the wrong size

[tom4bren]

"I greased my U joints this evening, but I could get much to even penetrate the zerk... weird."

Two thoughts:

1) they don't hold much grease - just a small hole down the length of each leg of the cross to allow the grease to get out to the bearing cups (also happens to be the outer race). The cups aren't that big & they are pretty full considering that they cover the needle bearings and the ends of the cross (inner race). Basically the only room for grease is the area around the needle bearings.

2) without regular service (grease) the bearings could have gotten hot enough to 'cook' the grease & make it harden. You can't force new in if you can't push the old out.

I had an old Dodge & the U Joints didn't have Zirk's. When I finally went to replace, guess what ... no grease in the cups & no needle bearings either - just rust colored dust.