U-Joint question

[Tom Schindler]

We have a vibration on our 2000 Explorer 4x4. If you apply throttle, starting at about 25 MPH, we get a vibration. If I let off the throttle, the vibration goes away.



It has been a rough winter and for some reason, winter does not want to go away (Global warming I guess:banghead. Anyways, it is getting worse and I will need to take the car off the road to get it fixed.



Does this sound like a U-joint issue? The vehicle only has 209,500 miles on it, so it is still in its prime.



Is there an easy way to check the U-Joints? Are they easy to install?



Any help would be appreciated.





Tom

 

[Jerry Gerner 2]

If their factory, I'm amazed they lasted this long !!!!



Their pretty easy to do but you need the front u-joint on the driveshaft needs to be pressed in and out.

 

[David Ponder]

Does it still do it when you are rolling along and shif it into neutral? Not that I have had a lot of U-joints fail, but normally I would think they would have the vibration under load either way. (Load pushing or engine drag) If it only has the vibration under load, maybe a motor mount? Does the engine move considerably when you power brake it? Just a thought.

 

[Richard L]

It could be a U-Joint, but most U-Joint failures tend to start with a clunk when you accelerate and decellerate. Then they start to make a squeak/squeal noise, in sync with the rotation of the shaft.



The bad winter means you may have hit a snow drift or large clump of ice that may have bent or dented the driveshaft causing the unbalanced condition.



Looking at the driveshaft, you should be able to feel and/or see any dents. A slight bend may be harder to spot and will require a strait-edge to see any bowing.



The last thing, that probably should be checked first is the tires. I have had a number of tires that wore out-of-round and it took a dial-indicator to detect the defect. If the bad tire is on the front, you will feel the vibration through the steering wheel. If it's on the rear, you will feel the vibration in the seat of your pants in more of an Up-and-down vibration.



...Rich

 

[Craig Martin 2]

I just went through that issue. Climb under it and grab the drive shaft. Look at the drive shaft while moving it with your hand. If you see the area where the joint is moving then I'm 100% sure its the drive shaft. I ended up having to take it to a friends shop to get the bolts taken off. Stupid rust. I was lifting my 330lb ass off the ground trying to break the bolts loose, and that was after soaking them with penetrating oil AND a 17 inch Johnson bar!!! There was RED lock tight on them from factory. After the shaft was out it was a breeze getting the old one out and the new one in. There is a couple videos I found on youtube IIRC and there is a mechanic that shows the average guy how to do it. Fairly easy once you know how.



Good luck!

 

[EddieS'04]

Tom, put a large screw driver or punch. Into the yoke were the U's are. Work it back and forth. Look for movement.



Just my experince is. The front U on the main shaft has always gone out first on me. With high milage I replace both.

 

[Kevin Palmer]

Tom, if you find it is the UV joints, let me know.



I have replaced probably over 1000 at my shop. If we can mesh our schedules, I will be glad to help you...



Well,,,, not sure about glad,,, But I will help...

 

[EddieS'04]

I have replaced probably over 1000 at my shop

Almost as many as me. During my racing days. I have damaged u's, Broken yokes on both ends and riped the eyes out of drive shafts...LOL

 

[Tom Schindler]

It is the u joints. I pulled the shaft (really easy to do) and when everything was loose, the rear joint was pretty bad. I am going to replace both joints.



I checked out some youtube videos and it looks pretty easy to swap out the joints. Will do that tomorrow morning after I get home from work.





Tom

 

[Richard L]

Caymen,

A large "C-clamp" or a vise is very helpful in pushing the U-joints out.



If they were that loose, they should have been giving a very noticable "Clunk" when you step on the gas or let off the gas.



...Rich

 

[Tom Schindler]

If they were that loose, they should have been giving a very noticable "Clunk" when you step on the gas or let off the gas.

I would expect that too. Unfortunatly there was no clunk. All that pointed to the U-Joint was when you applied power, there was a very pronounced vibration. Once you let off the gas, the vibration would go away.



Even when everything was together, there was no looseness on the joint. Only when I pulled the bolts off of the differential, could I feel the looseness. I will be replacing both the front and rear joints on the rear driveshaft.





Tom

 

[Tom Schindler]

U-joints changed out. It was pretty simple. After I got the first one, the second one was a dream.



If I knew what I was doing when I started, it would have been together in no time.



Thanks for all of your help. It was greatly appreciated!





Tom

 

[Kevin Palmer]

Cool,,, glad you got them changed out with no real issues...