Only one wheel spins with rear axle jacked up

[cgollmd]

I've searched extensively for an answer to this so, I apologize if it's posted somewhere and I'm missing it. I just bought a used 2015 Wrangler Sport. I can't seem to get a hold of the window sticker or build sheet but the seller told me he believes it has a limited slip differential. When I jack up the rear axle I can easily turn either wheel but, the other wheel does not spin in the same or opposite direction. It just stays at rest

. The drive shaft rotates freely when I rotate either wheel. The Jeep drives perfectly normally in two-wheel or four wheel drive.

Do I have LSD or just a regular open diff or an LSD that's defective? I've attached a picture of the differential cover.

Thanks in advance for your guidance.

 

[Danarch]

You can enter the VIN number here and it will give you the full build sheet.

https://fcagroup.my.site.com/RAM/s/equipment-listing

 

[cgollmd]

Very helpful, thank you. According to my build sheet the Jeep has a conventional differential on the front and rear. So, with the rear end jacked up, if I spin one wheel forward I would expect the opposite wheel to spin backward. Should I be concerned that this does not happen?

 

[SteveF]

That is called an open differential. When I re-geared my axles I put in a limited slip differential (positive traction) . My build sheet said I had 3.73 gears but turned out to be 3.21. I upgraded to 4.56 gears

 

[cgollmd]

Thank you for your reply.
When the rear axle is jacked up: I thought that with an open differential, when the right wheel is spun forward, the left wheel will spin backwards and vice versa.
With posi-trac the wheels spin the same way when either is spun.
I'm just not familiar with the opposite wheel doing nothing at all while spinning rear one.

 

[Dirty Dog]

You are correct. With an open diff, the wheels should spin in opposite directions. My first guess would be brakes stuck or dragging.

 

[cgollmd]

Both wheels spin easily and freely so I don't think it's brakes or other drag source. I noticed that when I spin either wheel, the drive shaft is spinning. I suspect if I put it in gear or hold the drive shaft still, I'll see the expected counter rotating behavior of the wheels. I'll try it over the weekend.

 

[BLACKJKU]

Both wheels spin easily and freely so I don't think it's brakes or other drag source. I noticed that when I spin either wheel, the drive shaft is spinning. I suspect if I put it in gear or hold the drive shaft still, I'll see the expected counter rotating behavior of the wheels. I'll try it over the weekend.

You could pull the cover off and look then you'll also know what gears it has, more than likely it's never had the oil changed anyway.