D30 Grinding on the ZJ - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > D30 Grinding on the ZJ

Rockridge 4WD IS Taking Zone Offroad Suspension Lift Kits ZONE 4.25" combo lift for TJ available at Rockridge4wG2 Disc Brake Conversion Kit for Jeep Wrangler YJ TJ LJ Ch

Reply
Unread 12-26-2012, 05:10 PM   #1
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
D30 Grinding on the ZJ

What I thought sounded like a wheel bearing turned out to be coming from my front diff on the ZJ. The sound has been getting worse and worse; been running in 2wd but in 4 all time it's unbearably loud. It sounds like some sort of bearing problem, just a loud grinding from 20-30 mph and then a loud groan any faster.

I took the fill plug out to see if perhaps it was low on oil. Instead, a thick sludgy black/greenish oil oozed out. I changed the oil and gaskets a few months ago, so obviously something's wrong.

Any ideas? It's winter here so almost no chance of doing any work myself. Are we talking a rebuild here?

__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Unread 12-26-2012, 05:34 PM   #2
flexyxj
Registered User
2009 XK Commander 
 
Join Date: May 2005
Location: Sioux Falls,SD
Posts: 491
The ring and/or pinion is probably gone. Pull the cover and look. It's probably time to find a different front diff.
flexyxj is offline   Reply With Quote Quick reply to this message
Unread 12-26-2012, 05:55 PM   #3
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
What does than entail? A complete axle swap?

I'm on a pretty tight budget right now, and it's the middle of winter here so no junkyards or anything.
__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Unread 12-26-2012, 06:11 PM   #4
flexyxj
Registered User
2009 XK Commander 
 
Join Date: May 2005
Location: Sioux Falls,SD
Posts: 491
That would be my best guess.If you pull the front cover - you'll know for sure. It could possibly be the front carrier and pinion bearings but from your description,it's probably too far gone already.......
flexyxj is offline   Reply With Quote Quick reply to this message
Unread 12-26-2012, 06:54 PM   #5
ratmonkey
R.I.P.
 
ratmonkey's Avatar
1997 ZJ 
 
Join Date: Dec 2006
Location: , Pennsylvania
Posts: 19,794
Probably the gears by now. Much easier to swap the whole axle.
__________________
'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.

ratmonkey is offline   Reply With Quote Quick reply to this message
Unread 12-26-2012, 06:55 PM   #6
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
I don't even want to pull the cover and waste money on new oil and gasket when I have to reseal it... So sick of stuff breaking on this Jeep.

Axle swap is an option I guess...
__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Unread 12-26-2012, 07:00 PM   #7
xcaliber81
Registered User
1994 ZJ 
 
Join Date: Jul 2012
Location: Prince George, B.C
Posts: 3,072
sorry for hijacking your thread but when i put my jeep in 4wd since i rotated my tires i have developed a humm could this just be my tires or do i have a front diff problem also? I had a free tire rotation at a tire shop so i don't know how they rotated them.
xcaliber81 is online now   Reply With Quote Quick reply to this message
Unread 12-26-2012, 07:45 PM   #8
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
Well, I would imagine if your diff oil is fine and you're not hearing any groaning or grinding, you're probably fine and it's just your tires.

Anybody know how much it costs to get a shop to redo the bearings in a diff? I've read that a rebuild is close to 800$; with the Junkyards all pretty much closed (average temp is like 8-10 Fahrenheit these days) I don't know how I'd find an axle used.

At this point it's becoming a chore to keep the ZJ running well. I'm spending well over 250$ a month on parts alone, and there is tons left to do... Considering just selling the thing, although I love it, and buying a newer cheap 2wd Ranger...
__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Unread 12-30-2012, 01:00 PM   #9
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
I called a local transmission/diff shop. The guy said without having a look yet a rebuild can go anywhere from $500 to $1200.

I'm going to shop around.

Anybody know if just changing the bearings would help, even if the gears are slightly worn since all this?
__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Unread 12-30-2012, 01:07 PM   #10
flexyxj
Registered User
2009 XK Commander 
 
Join Date: May 2005
Location: Sioux Falls,SD
Posts: 491
Quote:
Originally Posted by ZJMTL View Post
I called a local transmission/diff shop. The guy said without having a look yet a rebuild can go anywhere from $500 to $1200.

I'm going to shop around.

Anybody know if just changing the bearings would help, even if the gears are slightly worn since all this?
Changing bearings won't do much good because with what you've described there probably isn't much left in the way of gears. Pull the front cover. You'll know what you need to do. If the gears look good and there's no teeth missing,then maybe bearings would take care of it. You could have something wrong with the front carrier too.
flexyxj is offline   Reply With Quote Quick reply to this message
Unread 12-30-2012, 08:57 PM   #11
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
Carrier meaning bearing? I'm still running it in 4wd when needed (2wd is useless in the snow here) and it works like it should. I'll have to drop the cover I guess and go from there.
__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Unread 12-30-2012, 09:03 PM   #12
flexyxj
Registered User
2009 XK Commander 
 
Join Date: May 2005
Location: Sioux Falls,SD
Posts: 491
It could be bad pinion or carrier bearings or maybe bad u-joint in one of your front axle shafts or bad u-joints in your front driveshaft.
flexyxj is offline   Reply With Quote Quick reply to this message
Unread 12-30-2012, 09:18 PM   #13
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
Pretty sure the bearings are just toast in the diff.

If it changes anything, there seems to be little to no play in the front DS. The noise is also not a high pitch squeal indicative of a pinion bearing but more of a hum/rumble/groan, kind of like a bad wheel bearing.

My real question is, if my 4x4 is working like it should now even with the bad bearings, and I DO happen to find some metal shavings in the oil, is it completely necessary to change the gears? Or will replacing the bearings suffice?
__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Unread 12-30-2012, 09:36 PM   #14
flexyxj
Registered User
2009 XK Commander 
 
Join Date: May 2005
Location: Sioux Falls,SD
Posts: 491
It depends on what the gears look like..... I'm assuming it's an open front diff. If that's the case,you might have something going on with the spider gears in the carrier. The longer you run it the way it is,the more damage you will do....
flexyxj is offline   Reply With Quote Quick reply to this message
Unread 12-31-2012, 11:35 AM   #15
ZJMTL
Registered User
1996 ZJ 
 
Join Date: Feb 2012
Location: Montreal, Quebec
Posts: 1,251
Thanks for the reply! I'll stop driving it until I can pull the cover.
__________________
'96 Laredo Build Thread - http://www.jeepforum.com/forum/f197/zjmtls-project-thread-daily-driver-weekend-getaway-vehicle-1360544/
ZJMTL is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

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.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.