Vibration when in 4WD-FT -
LinkBack Thread Tools
post #1 of 4 Old 10-09-2004, 06:55 PM Thread Starter
Registered User
Join Date: Oct 2004
Posts: 3
Vibration when in 4WD-FT

I have a stock 2001 GC Laredo w/ 55K. I have the Selec-Trac TC, not sure what the NP number is.

When I put it in 4WD Full Time, I have a vibration right under my feet. I am not a car guy, but I was thinking drive shaft or u-joints?

The thing is, the way I understand it, is that there are no hubs in the Jeep, so the axle and drive shaft are always turning, so why does it not happen, when I am in 2WD?

Anyway some history:

Just had the differential rebuilt, bearings and spacers and nut pinion.

And two weeks after that, it was leaking diff fluid, brought it back to the dealer, and they replaced the pinion seal.

Could they have screwed up on the diff? I will be bringing it back this week to the Jeep dealer, thank god I bough a 3/36k warranty, even if it is from "joe blow", they paid for the diff rebuild

Anything to give me some piece of mind that my truck is now screwed up beyond belief, is greatly appreciated.

- John

jrdicker is offline  
Sponsored Links
post #2 of 4 Old 10-09-2004, 07:12 PM
Registered User
1996 ZJ 
Join Date: Apr 2003
Location: Belle, WV
Posts: 4,930
You have the NP242 transfer case.

The way I am reading your post, everything was fine until you took it in to have the diff rebuilt, then the vibration started.
Sounds to me like the shop messed up.

Your driveshaft and front axles are equipped with CV-joints except for where the driveshaft connects to the TC, that utilizes a double cardon joint (two U-joints working together).
When you are in 2WD, your TC and differential are both open, so there is no torque being delivered to the front axles, therefor your front driveshaft does not spin. Any out-of-balance condition wouldn't show up in 2WD, but would in 4WD. I wouldn't rule out incorrect installation of the gears inside the diff though. After all, they weren't even able to seal the cover!


Black 1996 5.2L ZJ Limited
Meerkat is offline  
post #3 of 4 Old 10-09-2004, 07:44 PM Thread Starter
Registered User
Join Date: Oct 2004
Posts: 3
Thanks a ton Warren!

You made be feel so much better by just giving me more information on how the GC works.

I will go to the dealership on Monday to make another appointment, you know, I thought brining the GC to a Jeep Dealership, would be the best thing, I am second guessing my action now.

But again, thanks so much for the quick thorough answer, you are definitely an asset to this forum.

I will post my whatever the fix is, as soon as I get it serviced again.

- John
jrdicker is offline  
post #4 of 4 Old 10-09-2004, 07:52 PM
Registered User
1996 ZJ 
Join Date: Apr 2003
Location: Belle, WV
Posts: 4,930
The problem with shops is that mechanics are people, and like any other profession, some are more skilled than others even if they hold the same certifications. Additionally, I have no doubt they are pressured to repair the greatest number of vehicles in the least amount of time. If not by the shop manager, certainly by customers that expect their vehicle to be ready ASAP.
Unfortunately, sometimes you have no choice but to take your vehicle to a shop to be worked on.
I am looking forward to hearing how your problem is resolved. We always appreciate follow-up posts!

Black 1996 5.2L ZJ Limited
Meerkat is offline  

Quick Reply

Register Now

In order to be able to post messages on the forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
vibration rmtomasin ZJ Grand Cherokee Forum 11 03-26-2009 09:40 PM
vibration driabyor ZJ Grand Cherokee Forum 5 06-23-2005 09:24 PM
I6 vibration... CBlakeNS ZJ Grand Cherokee Forum 13 04-20-2005 09:43 PM
Vibration at 65+ MPH ats1968 ZJ Grand Cherokee Forum 1 02-12-2005 11:15 PM
vibration 01grander ZJ Grand Cherokee Forum 3 01-18-2005 07:34 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome