2X Front drive shaft blown in 2 days

Katana · **Posted:** Mon Jan 25, 2010 8:58 pm

Hi there

I'm new to the forum and have owned a TJ for about 6 years but I recently purchased a stock 2004 Kj Limited Petrol in Auto with 75K on it

. But it seems to be blowing the front drive shaft on the transfer case side. :cry:

The first day I got it I noticed a very slight vibration coming from the front end only when engaged in full time / part time 4wd. This vibration will continue for some time even after it has been shifted into 2wd. The vibration and the pull to the left only stops if i do a u turn or reverse in the same manner till I hear and feel a large clunk from the transfer case.

The following day still feeling the slight vibration in 2wd. I jumped on the motorway on my way up to work and while sitting on appox 110km/hr the slight vibration got worse to the point where the steering wheel started to vibrate almost like a death wobble at which point I noticed smoke from the front end - with an accompanying rattling / grinding noise.

I had the dealer look at it and they replaced the front drive shaft 2 days ago. Today coming back from doing a bit of wheeling I below another drive shaft on the freeway in 2wd after being in '4wd part time' on the track the same issue occured. The severe vibration followed by smoke.

It feels like it not disengaging 4wd as I noticed a slight pull to the left causing the whole system to bind and eventually killing drive shaft.

I'm feeling that the root cause of the problem may not lie with the front drive shaft and some other underlying problem is causing it to blow it

Before i take it into the repairers again, just wondering if anyone has had similiar issues?

Cheers

JeepinJarhead03 · **Posted:** Mon Jan 25, 2010 9:35 pm

do you know which transfer case you have?

the 231 command trac 4wd system is a part-time 4wd system in which, short of a detailed explanation, the front wheels turn slightly faster than the rear when 4wd is engaged causing destructive binding throughout the system when part-time is used on a tractioned surface

if you have the 232 or full-time 4wd system this binding shouldn't be occurring and the problem isn't likely to lie with the type of use or driver related circumstances and would be symptom of another problem in the system

the part time systems will typically have difficulty un-engaging if the stresses on the front wheels is not equal, for instance, one tire being slightly larger due to being newer or an entirely different tread type in which case, what i call a "wrangler roll-back" or driving the vehicle backwards a few feet after disengaging, to make double sure 4wd is disengaged is pretty much my standard operating procedure

ATXKJ · **Posted:** Mon Jan 25, 2010 9:48 pm

Howdy - welcome to LOST

If you have a Full Time 4wd - then you have the 242 transfer case

unfortunately the shift lever pushes a spring which pushes a gear - so if there is any difference between front and rear tires - size/ wear/ air pressure - the gear either will not engage - or will not disengage - although the shift lever will be in the correct position.

make sure everything matches front to rear.

Katana · **Posted:** Mon Jan 25, 2010 10:10 pm

Thanks for the quick response JeepinJarhead and thanks to the warm welcome. I believe the transfer case i have is the 2nd one that you mentioned as it has 2wd - 4wd Partime - 4wd full time - N - Low range.

Like you said it I'm also guessing that its not releasing from part time 4wd since the transfer from any mode of 4wd to 2wd has to pass thought part time 4wd.

I had a good look at the tires and the front and the back are are the same 235/70/16 but different make and the rear are almost down to the the last 10% of its tred whilst the front are almost brand new. Could that be causing of all the hassles with getting it into 2wd?

tjkj2002 · **Posted:** Mon Jan 25, 2010 10:13 pm

Katana wrote:

Thanks for the quick response JeepinJarhead and thanks to the warm welcome. I believe the transfer case i have is the 2nd one that you mentioned as it has 2wd - 4wd Partime - 4wd full time - N - Low range.

Like you said it I'm also guessing that its not releasing from part time 4wd since the transfer from any mode of 4wd to 2wd has to pass thought part time 4wd.

I had a good look at the tires and the front and the back are are the same 235/70/16 but different make and the rear are almost down to the the last 10% of its tred whilst the front are almost brand new. Could that be causing of all the hassles with getting it into 2wd?

Yep your tires are your issue,the tires can not be more then about 5%(at max) difference in overall diameter(includes tread depth and air pressure) or shifting problems will occur with that t-case.

JeepinJarhead03 · **Posted:** Mon Jan 25, 2010 10:15 pm

that could very well be what's preventing it from releasing

for the time being until you can fix the tire situation, sounds like you need two new rear tires,

try backing up about 5 feet after pushing it into 2wd, it's something we typically had to do with the wranglers from time to time to get them out of 4wd

4wd Part-Time binding on the pavement sounds like whats busting your drive shaft, honestly i'm surprised it didn't bust the transfer case too if that is indeed the case

Jeepjeepster · **Posted:** Mon Jan 25, 2010 10:31 pm

Theres no doubt thats part of the problem if not all of it. It pulling to the left is kinda confusing. If its getting stuck in 4wd Im not sure how that would cause it to pull to the left.

That is probably whats leading to or at least helping kill the front drive shafts also. Hopefully if its been stuck in part time its not hurt anything else. Driving it in part time like that at high speeds can really do some damage to the drive train.

Katana · **Posted:** Mon Jan 25, 2010 11:18 pm

Cool thanks guys at least that's an easy fix.

But just in regards to the minor vibration issue in 4wd is that normal? When I say minor I can just feel it thought the floor on the drivers hand side. But when it manages to get into 2wd its smooth as silk.

Thanks again for the quick response guys.

JeepinJarhead03 · **Posted:** Mon Jan 25, 2010 11:29 pm

the vibration could be a symptom of some damage done to the 4wd system, damage done to CV joints at either front wheel, or to the rear ujoints or the transfer case itself

make sure you get the transfer case drained, flushed a bit then refilled with some fresh ATF4, if there was some minor damage internally to the transfer case you certaintly don't want that metal flake circulating around, plus the heat that can build up due to using PT 4wd on a friction surface can really cook the fluid

i would start with draining and refilling the transfer case, and while you, or whoever, is crawling around, check the front cv's for play, torn boots, oozing grease and what not

Jeepjeepster · **Posted:** Mon Jan 25, 2010 11:50 pm

Yes, a slight vibration is normal in 4wd(hopefully youre in full time on blacktop). You should be able to feel it under acceleration only though. If its vibrating all the time when in 4wd when you may have something else going on.

tjkj2002 · **Posted:** Tue Jan 26, 2010 12:32 am

Jeepjeepster wrote:

Yes, a slight vibration is normal in 4wd(hopefully youre in full time on blacktop). You should be able to feel it under acceleration only though. If its vibrating all the time when in 4wd when you may have something else going on.

Any vibs in 4wd in not normal,even if accelerating.

djui5 · **Joined:** Tue Jun 17, 2008 1:38 am **Posts:** 536

When you replace the front DS again, make sure you get one with u-joints

FreedomKJ · **Posted:** Tue Jan 26, 2010 2:00 pm

djui5 wrote:

When you replace the front DS again, make sure you get one with u-joints

Replacing the front CV driveshaft with one using U-joints will cause more vibration. Vibration isn't just a comfort issue, it will have a detrimental effect the life of your differential and transfer case as well.

Jeepjeepster · **Posted:** Tue Jan 26, 2010 2:36 pm

tjkj2002 wrote:

Jeepjeepster wrote:

Yes, a slight vibration is normal in 4wd(hopefully youre in full time on blacktop). You should be able to feel it under acceleration only though. If its vibrating all the time when in 4wd when you may have something else going on.

Any vibs in 4wd in not normal,even if accelerating.

Odd. Our xj and my kj both have the same vibration in full time. Both had it from the factory.. Actually every jeep Ive been in has done that in full time. Its more of a roar than a vibration although I can feel it. Guess I should be careful when I say 'vibration.'

Katana · **Posted:** Tue Jan 26, 2010 8:37 pm

FreedomKJ wrote:

djui5 wrote:

When you replace the front DS again, make sure you get one with u-joints

Replacing the front CV driveshaft with one using U-joints will cause more vibration. Vibration isn't just a comfort issue, it will have a detrimental effect the life of your differential and transfer case as well.

My thoughts exactly. I'm concerned about the effect that it will have on the other running gears, my previous jeep was a mildly modified TJ running 33" but even with the lift and the bigger tyres I never felt any vibration. What I find unusual is that the KJ is only vibrating in 4wd and never in 2wd.

But going by what I've read it almost sounds like some of us just have it and live with it, and some don't experience vibrations at all.

Anyways I just got off the phone with the dealer and I got told not to exceed 60km/h in 4wd part time or full time on any surface and that the reason for the vibrations....... :ROTFL:

FreedomKJ · **Posted:** Wed Jan 27, 2010 12:48 am

Katana wrote:

FreedomKJ wrote:

djui5 wrote:

When you replace the front DS again, make sure you get one with u-joints

Replacing the front CV driveshaft with one using U-joints will cause more vibration. Vibration isn't just a comfort issue, it will have a detrimental effect the life of your differential and transfer case as well.

My thoughts exactly. I'm concerned about the effect that it will have on the other running gears, my previous jeep was a mildly modified TJ running 33" but even with the lift and the bigger tyres I never felt any vibration. What I find unusual is that the KJ is only vibrating in 4wd and never in 2wd.

But going by what I've read it almost sounds like some of us just have it and live with it, and some don't experience vibrations at all.

Anyways I just got off the phone with the dealer and I got told not to exceed 60km/h in 4wd part time or full time on any surface and that the reason for the vibrations....... :ROTFL:

They told you not to drive over 60km/h in full time? It's nice that dealers always know what they're talking about. </sarcasm>

djui5 · **Joined:** Tue Jun 17, 2008 1:38 am **Posts:** 536

FreedomKJ wrote:

djui5 wrote:

When you replace the front DS again, make sure you get one with u-joints

Replacing the front CV driveshaft with one using U-joints will cause more vibration. Vibration isn't just a comfort issue, it will have a detrimental effect the life of your differential and transfer case as well.

Not if it is balanced properly and uses double cardan joints. The double cardan joints allow for the angles that the CV was designed for. http://www.rblewis.net/personal/bronco/driveshaft/

My comment was more in regards to the breakage of the cv drive shafts than the vibrations.

dgeist · **Posted:** Wed Jan 27, 2010 3:49 pm

FreedomKJ wrote:

They told you not to drive over 60km/h in full time? It's nice that dealers always know what they're talking about. </sarcasm>

X2. I routinely drive ~120 kph or more in full-time with the 2.8 with no more vibration than I would fell in 2WH.

FreedomKJ · **Posted:** Wed Jan 27, 2010 5:52 pm

djui5 wrote:

FreedomKJ wrote:

djui5 wrote:

When you replace the front DS again, make sure you get one with u-joints

Replacing the front CV driveshaft with one using U-joints will cause more vibration. Vibration isn't just a comfort issue, it will have a detrimental effect the life of your differential and transfer case as well.

Not if it is balanced properly and uses double cardan joints. The double cardan joints allow for the angles that the CV was designed for. http://www.rblewis.net/personal/bronco/driveshaft/

My comment was more in regards to the breakage of the cv drive shafts than the vibrations.

A double cardan driveshaft will only help with vibrations if the pinion is aligned straight with the driveshaft. The front pinion on the KJ is horizontal and there is no way to rotate the diff, preventing a double cardan shaft from working properly.

Unfortunately without major drivetrain modifications a CV drive shaft is really the only good option for the KJ.

tjkj2002 · **Posted:** Wed Jan 27, 2010 10:24 pm

The correct angles for a single u-joint driveshaft so no vibes occur.............

The correct angles needed with a double cardon(CV) driveshaft so you get no vibes..............

2X Front drive shaft blown in 2 days

Who is online