Front drive shaft

[Midgear]

sorry for the long read-

alright, I looked and really didn't find much.. aside from where to get one and that the boot falls off of them or gets cut.. and stuff.

what I'd like to know is how the front drive shaft is set up, and how hard it would be to fix the one I have, replace it with a new one.. mabey grease it and call it good (which I seriously doubt)... are they a U-joint setup? or like a CV axel?

I read that the drive shaft constantly spins, regardless if 4WD is engaged or not- which makes me really wonder what the hell is going on.. I hope it's not my transfer case!

ONLY when I have 4WD engaged, I feel and hear this absolutely hideous metal scraping / clunking / grinding noise.. it sounds like a bearing or something is about 2 or 3 rotations away from complete failure or locking up.. but when 4WD is disengaged, it doesn't make a peep.

My guess is that something in the front drive shaft really doesn't like having torque applied to it, or a gear in the transfer case is fixin to take a massive dump.. It sounds like it's coming from right underneath the drivers seat (I can't look under it while it's rolling.. that'd be ******** and unsafe lol)

this metal grinding and clunking sound isnt constant, it seems to happen in a certain part of the revolution on the shaft, and when it gets to grinding and clunking, it's not quiet.. its very loud and it actually slows the Jeep down from an idle roll to a stand still..

what are my options here?

 

[JeepJeepster]

You can check the front drive shaft out fairly easy. Just crawl under there and check the boots(both at the tcase and the diff). Also, there shouldnt be any play up and down or side to side(rotational play is ok).

 

[Midgear]

http://www.car-stuff.com/store/?N=10856+4294962568+1557+11921+5568 LOOOLLLLL almost 600 dollars for a drive shaft.. what the hell. where's that one for $185 at.. ? --

You can check the front drive shaft out fairly easy. Just crawl under there and check the boots(both at the tcase and the diff). Also, there shouldnt be any play up and down or side to side(rotational play is ok).

If there is play, this means what.. bearings? joints replaced? is that possible without purchasing a whole new shaft?

If there ISN'T play, where and what do I look for?

 

[Blue KJ in PA]

Yes it spins all the time and the noise you hear when engaged is because now there is the torque from "locking in" the front wheels. Tommudd got a reman one from a place in Jersey that has served him well. I got mine replaced by the 7/70 warrranty for $100 deductible. Others have gone with a u-joint shaft but that leads to a vibration which is why Jeep put in the CV joints.

 

[Midgear]

So replace the entire shaft from the place in Jersey and be done with it then.. ?

What's the worst that could happen while using 4WD while its grinding along.. could it snap and disconnect or would it just fail to transfer torque to the front wheels?

The roads are currently covered in ice and snow and I'm at work and going to leave here in about 2 hours.. should I keep it out of 4WD or can I use it and just deal with the grinding?

 

[tjkj2002]

What's the worst that could happen while using 4WD while its grinding along.. could it snap and disconnect or would it just fail to transfer torque to the front wheels?

The roads are currently covered in ice and snow and I'm at work and going to leave here in about 2 hours.. should I keep it out of 4WD or can I use it and just deal with the grinding?

It could seize,taking out the t-case,front diff,and possibly the transmission.

Or............

It could break and fling around breaking the trans,front diff,and much,much more.

 

[JeepJeepster]

Yeah if its making that much noise I would stay in 2wd as much as you can. Just take it nice and easy and only use it if needed at low speeds.

 

[Midgear]

Reason I ask that ^^^ --

the grinding seems to be coming from the rear of the shaft that connects to the transfer case, but it -could- be coming from the front..

now, if using 4WD is going to eventually cause it to completely separate from the splines, if the front falls and hits the ground and catches on the pavement, god bless my undercarriage.. but if it falls from the back (where I believe the point of failure will be) , it'll just drag along on the ground.. well, no it won't.. because the front diff will still cause it to spin, which means it's gonna flail around like a ball and chain on crack.

so.. the question is.. use 4WD, or don't.. ?

Yeah if its making that much noise I would stay in 2wd as much as you can. Just take it nice and easy and only use it if needed at low speeds.

ah, ok.

how hard is it to remove the drive shaft?

 

[tjkj2002]

Don't,and it can still fail in 2wd.

 

[Midgear]

It could seize,taking out the t-case,front diff,and possibly the transmission.

Or............

It could break and fling around breaking the trans,front diff,and much,much more.

yeesh.. didn't see that post till just now. Sounds like I need to get it out of there as soon as possible then.. ? what kinda tools are we lookin at to get it off?

 

[Midgear]

my last and final question.. can the Jeep be driven without the front driveshaft in place? will I loose fluid anywhere?

 

[Midgear]

bump.. I leave work in 20 minutes, need to know the above^ ! and thanks for all your timely responses, appreciate it. I don't have internet access at my house (lol unreliable satellite..), so I'll probly be taking this thing out tomorrow if I can drive around without it.

 

[Midgear]

thank ya Budke for that insanely quick response. I'll let you guys know what horrifying things I find once the shaft is removed. I'll take pictures too.

 

[JeepJeepster]

Yes, you can drive in 2wd with the front DS out. Just make sure and keep it in 2wd

Removing the front DS isnt too bad on 2004+ libertys. On 2002 and some 2003 you may need to unbolt the exhaust to get it out.

 

[yellocoyote]

Not necessary to do anything with the exhaust on an '02 (not sure what the year of the OP's kj is). Just unbolt - 6 bolts front, 6 bolts rear, and wiggle the driveshaft out from above the exhaust. Done. Real easy.

 

[Midgear]

well I got it out, and let me tell you the bearings on the transfer case end of that shaft are absolutely shot.. they almost look like rocks instead of bearings LOL, there wasn't a smidge of grease in there either.. in fact, water poured out of it when I flipped the drive shaft around in my hand.. guess H20 doesn't make a very good lube

It wasn't too hard.. the most difficult part was telling myself im gonna have to lay on the wet icy ground to get up underneath there and get those bolts loose.. once the bolts were out, I tapped the back of the shaft (transfer case end) with a pry bar and a hammer and it fell out of the socket, wiggled the diff end loose and it fell to the ground, worked it passed the exhaust and clunk.. the entire shaft lay lifeless on the ground.

Didn't remove any other bolts aside from the shaft itself..

now that that mess is done with.. I noticed there's a large amount of grease in the diff end of the socket..( I popped the cap off the diff end of the shaft to make clearance for it to fall, which it helped, at the cost of a large mess of grease everywhere.) which is most likely gonna be flinging around as it spins.. but to hell with it.. I'll detail the Jeep once all this rain / snow / sleet / ice moves on and it dries up a bit.

hopefully putting the new shaft in will be as easy as taking it out

 

[Midgear]

ah which brings me to my next question.. is there any specific torque specs to go by or tightening pattern when putting this thing back in ?

 

[ThunderbirdJunkie]

If you break the bolt, you got it too tight.

 

[tommudd]

You want to make sure that you pull them all in tight, it can get off centered a bit, I just cranked mine down tight, they are not very big bolts so....

 

[brucebotti]

If you break the bolt, you got it too tight.

Hey TBJ....is that your MO....tighten it until it breaks and then back off a 1/4 turn........sorry....I couldn't resist!
Bruce