249, VC and bunny hop. Why? - 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 > 249, VC and bunny hop. Why?

Stainless Steel Door Hinge PinsPoly Door Hinge BushingsSave at JeepHut on Smittybilt Soft tops

Reply
Unread 04-30-2013, 05:17 AM   #1
Adam86
Registered User
1998 ZJ 
 
Join Date: Dec 2012
Location: Birmingham, England
Posts: 62
249, VC and bunny hop. Why?

Why does the transfer case cause this?

If the t/c is just sending power to the axle and its the axles job to allow the wheels to rotate at different speeds why is it the t/c that causes the wheels to skip whilst turning?

Adam86 is offline   Reply With Quote
Unread 04-30-2013, 06:14 AM   #2
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: 5,417
Axles only split power between each side. Transfer case splits the power between front and rear. If the wheelhop happens in AWD mode, it means your viscous coupling is shot and needs to be replaced.

If the wheelhop happens in 4lo, it is normal behavior because in 4lo front and rear axles are locked together providing you with maximum traction.
__________________
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
Unread 04-30-2013, 07:07 AM   #3
Adam86
Registered User
1998 ZJ 
 
Join Date: Dec 2012
Location: Birmingham, England
Posts: 62
Ok so im getting wheel hop whilst turning is that down to the axle because they split power from side to side?

If you get wheel hop in a strait line its the transfer case?
Adam86 is offline   Reply With Quote
Unread 04-30-2013, 07:12 AM   #4
Snowfan2
Registered User
1998 ZJ 
 
Join Date: Jan 2012
Location: North of Amarillo, Tx
Posts: 518
If you get wheel hop in a straight line something is seriously wrong. When turning, the front tires follow a longer path than the rears, that is what causes the binding when they are locked together as with a blown VC.
Snowfan2 is offline   Reply With Quote
Unread 04-30-2013, 07:43 AM   #5
Adam86
Registered User
1998 ZJ 
 
Join Date: Dec 2012
Location: Birmingham, England
Posts: 62
Quote:
Originally Posted by Snowfan2 View Post
When turning, the front tires follow a longer path than the rears, that is what causes the binding when they are locked together as with a blown VC.
Perfect, that's the reasoning answer I was looking for!

Didn't know the vc locked when in low on the 4.0. Nice info cheers.

I just get a bit of hop whilest turning was just using strait line as an example lol.

Cheers all!
Adam86 is offline   Reply With Quote
Unread 04-30-2013, 08:01 AM   #6
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: 5,417
Quote:
Originally Posted by Adam86 View Post
Ok so im getting wheel hop whilst turning is that down to the axle because they split power from side to side?
No, like I just wrote you get wheelhop because of a failed VC.

Quote:
If you get wheel hop in a strait line its the transfer case?
You would only get wheelhop or binding driving in a staright line if you had different gear ratios in front & rear axles. There is no wheelspeed differences to account for when driving straight.
__________________
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




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.