Another np249 question - 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 > Another np249 question

LOCKERS!!!! - ARB, Auburn, Detroit, Eaton, OX, Spartan, YuRIGID LED Light Blowout Sale - All Sizes, All Series, all ECGS Black Friday Sale!!

Reply
Unread 06-18-2013, 07:59 PM   #1
Dubfire98
Registered User
1996 ZJ 
 
Join Date: May 2013
Location: Knoxville, Tn
Posts: 225
Another np249 question

So I was out doing some backyard crawling today and I attempted to climb some logs I had cut. I got the front left up to the first log and started up and then only my opposing tires front and back spun and I couldn't climb up even in LO range. Since its full time 4x4, would I have to lock both axles the same diff lock or could I just get away with a rear locker?

Dubfire98 is offline   Reply With Quote Quick reply to this message
Unread 06-18-2013, 09:18 PM   #2
a70eliminator
Registered User
 
Join Date: Dec 2004
Location: Kent Ohio
Posts: 864
I'm going to try to explain whats happening, the tire that IS getting traction, only gets the same torque of the opposing spinning tire, if one tire is in the air your going no where, that's why we like locking differentials, ok that takes care of the front and rear axles side to side power.
Now the transfer case works very similar only front to back rather than side to side and the viscous coupler can distribute the torque a little better than an open differential. So for hard core crawling the 249 with open diffs is not much use.
a70eliminator is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 02:49 AM   #3
Dubfire98
Registered User
1996 ZJ 
 
Join Date: May 2013
Location: Knoxville, Tn
Posts: 225
Well this is my daily rig and even tho I've got another crawler at my disposal, id like to possibly get a rear locking diff for the zj. My question is... Is this gonna be ok to do since its full time?
Dubfire98 is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 04:13 AM   #4
Timo_90xj
Web Wheeler
 
Timo_90xj's Avatar
1998 ZJ 
 
Join Date: Mar 2006
Location: Helsinki, Finland - on the European side of the Atlantic
Posts: 5,693
You can use any type of locker at the back with no issues, does no harm with the 4wd system or doesn't really affect handling much at all. If you have a D44a at the back, you don't have much choise on the lockers. IIRC aussie locker is the only lunchbox locker you can get for an open-carrier D44a, and no full carrier replacement lockers are available.


I wouldn't use an auto locker in the front though with the AWD, get a selectable if you like locking the front as well..
__________________
1998 Grand Cherokee 5.9 LX daily driver, 1.75" BB, 32" KM2s, HPD30 Eaton e-locker/D44a stock LSD, 4.56 gears, custom- fabbed tube bumpers and tube fenders,...

http://www.jeepforum.com/forum/f13/d...s-etc-1222317/


1990 XJ Limited (4-door), 4.0 I6, AW4, NP242, ***rolled and totalled @ 165k miles***

***Under construction***
1990 XJ (4-door), 4.0 I6, AW4, NP242, PBR 42" tires, Unimog 404 portal axles, 110" WB, full cage + uniframe completely rebuilt, front 3-link + panhard / double triangulated 4-link rear,... ***SOLD***
Timo_90xj is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 06:51 AM   #5
Technohead
Old School
 
Technohead's Avatar
1998 ZJ 
 
Join Date: Dec 2008
Location: Exeter, RI
Posts: 6,715
Quote:
Originally Posted by Dubfire98 View Post
Well this is my daily rig and even tho I've got another crawler at my disposal, id like to possibly get a rear locking diff for the zj. My question is... Is this gonna be ok to do since its full time?
Yes.
Technohead is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 11:43 AM   #6
tucsonzj
Registered User
2000 TJ Wrangler 
 
Join Date: Jul 2012
Location: Boston, MA
Posts: 2,153
Quote:
Originally Posted by Technohead View Post
Yes.
this^

If you want to lock, lock the rear first. Follow advice above. If you want to lock the front, go full out and do something like an ox where you can select on and off for daily use and tail days.
__________________
"washing it inside and out is on my to-do, eventually, maybe, if I have time, OOOH angle grinder."
tucsonzj is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 01:33 PM   #7
Dubfire98
Registered User
1996 ZJ 
 
Join Date: May 2013
Location: Knoxville, Tn
Posts: 225
Yea id really just like to lock the rear for the occassional trail ride/snow storm. Although really in knoxville it only snows good two days a year if that lol. its my dd and my boat hauler so really its not a need, just a want. But thanks for the input you guys!
Dubfire98 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.