Driveshaft question

[chuck2000xj]

Hey guys... Been awhile since I've been on. I have a question...I have been running a 3" lift on 33's with a T case drop for about a yr now. Over the last few months I have been getting a lot of vibrations coming from directly under the front seats. I'm wondering if there might be a problem with my rear driveshaft and how would I figure it out? Thanks

[Mudderoy]

Hey guys... Been awhile since I've been on. I have a question...I have been running a 3" lift on 33's with a T case drop for about a yr now. Over the last few months I have been getting a lot of vibrations coming from directly under the front seats. I'm wondering if there might be a problem with my rear driveshaft and how would I figure it out? Thanks

I had a really bad u-joint on my front drive shaft. When was the last time you changed the u-joints? Pretty cheap and fairly easy to do.

[chuck2000xj]

Its been a while. I guess I will take a look and change them anyway. Probably wouldnt hurt.

[4.3LXJ]

If you didn't have it before, and you have it now, then you probably have a bad u joint. Check them all. By the time it gives bad vibes it should be easy to find.

[chuck2000xj]

Recommendations on U joints?

[Metlic53]

Recommendations on U joints?

spicer is pretty popular :D

[chuck2000xj]

So there are 3 U joints in the front and rear drive shafts, correct?

[4.3LXJ]

Three in front and two in the rear unless it has been converted to a slip yoke eliminator.

[Firemanray]

And dont forget your front axle ends.

[Mudderoy]

Its been a while. I guess I will take a look and change them anyway. Probably wouldnt hurt.

Yep, about a week before I changed the front/front drive shaft u-joint I got up under the jeep, put my had on the drive shaft and I was able to turn it about 1/4 of an inch! I didn't know how bad it was until I got it out...

https://lh6.googleusercontent.com/-XUY0p0J8WAk/TnwK97C682I/AAAAAAAABPc/39KYFD0eS14/s912/2011-09-22%25252022.15.35.jpg

I didn't remove needle bearings prior to taking this picture, they just weren't there! Well in dust form I guess there were a few...

[chuck2000xj]

Wow that doesn't look good. So would the vibrations be coming from the front or rear driveshaft? I'm thinking rear because I'm not in 4x4 while driving and it's making the vibrations.

[Firemanray]

Wow that doesn't look good. So would the vibrations be coming from the front or rear driveshaft? I'm thinking rear because I'm not in 4x4 while driving and it's making the vibrations.

Yes but your front shaft still turns. Pop the front shaft out and go for a spin, that'll tell the tale.

[LizardRunner]

For the cost I like to just replace all U joints at the same time. I grease mine every other month unless I go swimming/mudding then I grease and change all the fluids as soon as I get home.