Wheels locked up
Hey everyone I need some help. I bought a 90 xj a couple months ago and it needed some love. I fixed it up a bit but during the first snow fall I put the 4x4 on and it felt like something was holding it back. Turns out the front right tire was locked up. So I brought it back home and now even the rear right tire is locking up. I tried to take it out of 4x4 but it wont come out. Im fairly new to working on 4x4 so I don't know what is going on. If anyone has any idea that would be great.
CF Veteran




Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
Check rusted solid parking brake cable to back brakes. Check all brake hardware for missing broke stuff.
Senior Member
Joined: Apr 2013
Posts: 781
Likes: 2
From: Dawson Springs, KY
Year: 1985
Model: Cherokee
Engine: 2.5L
Hey everyone I need some help. I bought a 90 xj a couple months ago and it needed some love. I fixed it up a bit but during the first snow fall I put the 4x4 on and it felt like something was holding it back. Turns out the front right tire was locked up. So I brought it back home and now even the rear right tire is locking up. I tried to take it out of 4x4 but it wont come out. Im fairly new to working on 4x4 so I don't know what is going on. If anyone has any idea that would be great.
Were you driving in the snow before you put it in 4x4 or were you on dry pavement?
If there are different gears front and rear, you could put it up on jack stands so all four wheels are off the ground and the stress should come off and allow you to take it out of 4x4 if nothing in the transfer case is broken.
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Do you have only 4Hi or 4Hi part time and 4Hi full time on the shifter?
Were you driving in the snow before you put it in 4x4 or were you on dry pavement?
If there are different gears front and rear, you could put it up on jack stands so all four wheels are off the ground and the stress should come off and allow you to take it out of 4x4 if nothing in the transfer case is broken.
Were you driving in the snow before you put it in 4x4 or were you on dry pavement?
If there are different gears front and rear, you could put it up on jack stands so all four wheels are off the ground and the stress should come off and allow you to take it out of 4x4 if nothing in the transfer case is broken.
CF Veteran




Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
Senior Member
Joined: Apr 2013
Posts: 781
Likes: 2
From: Dawson Springs, KY
Year: 1985
Model: Cherokee
Engine: 2.5L
If you have two different gear ratios, you have to either regear the front or the rear to match the other one.
Engaging 4x4 with different ratios causes the front and rear axles to rotate their wheels at different speeds. On dry pavement you won't go a few feet before the stress locks things up. On snow the wheels can slip and you will get a little further but the numerically higher ratio axle is turning slower and holding the other back, think pulling a kid in a wagon while they drag their feet. Eventually you will gain enough traction with all four wheels that it will cause the transfer case gears to bind up and you will stop.
If you can get all four wheels off the ground and they will spin when idlng in 4x4, then mismatched gears could be the problem. If they still don't spin then you have other problems.
If the front only had bad wheel bearings or brakes then it should have given problems even when in two wheel drive. If the parking brake cable was frozen, it is attached to the rear wheels and engaging 4x4 should not have caused everything to lock up, it would have been dragging just before you engaged. Bad U-joints in the front could cause problems, but unless you have a CAD axle, they should have been causing the same problem in two wheel drive.
You just have to imagine how each part works and how it is connected to the rest of the parts, then think how they interact if one breaks. This problem seems to be caused when the transfer case is engaged, so it is either internal to the transfer case or something due to the transfer case locking the front and rear axles together. Then work out from the transfer case to the wheels thinking how each part might affect the whole system.
Engaging 4x4 with different ratios causes the front and rear axles to rotate their wheels at different speeds. On dry pavement you won't go a few feet before the stress locks things up. On snow the wheels can slip and you will get a little further but the numerically higher ratio axle is turning slower and holding the other back, think pulling a kid in a wagon while they drag their feet. Eventually you will gain enough traction with all four wheels that it will cause the transfer case gears to bind up and you will stop.
If you can get all four wheels off the ground and they will spin when idlng in 4x4, then mismatched gears could be the problem. If they still don't spin then you have other problems.
If the front only had bad wheel bearings or brakes then it should have given problems even when in two wheel drive. If the parking brake cable was frozen, it is attached to the rear wheels and engaging 4x4 should not have caused everything to lock up, it would have been dragging just before you engaged. Bad U-joints in the front could cause problems, but unless you have a CAD axle, they should have been causing the same problem in two wheel drive.
You just have to imagine how each part works and how it is connected to the rest of the parts, then think how they interact if one breaks. This problem seems to be caused when the transfer case is engaged, so it is either internal to the transfer case or something due to the transfer case locking the front and rear axles together. Then work out from the transfer case to the wheels thinking how each part might affect the whole system.
CF Veteran
Joined: Feb 2016
Posts: 3,683
Likes: 8
From: Northern New Mexico
Year: 1999
Model: Cherokee
Engine: 4.0
go to 4wd and drive straight on grass or gravel. normal you can go. if 2 different gears you aint going.
that how to check it.
i just did it 5 minutes ago on my gravel drive and a SHORT way on the street!
in 2wd you could go,its like having no gears up front
that how to check it.
i just did it 5 minutes ago on my gravel drive and a SHORT way on the street!
in 2wd you could go,its like having no gears up front


