Unless there are new options the RDM has to be replaced as a whole unit, I thought only a couple of the seals were available as stand alone parts

 

Hey @Gremlin11 ,

That is VERY wobbly. The left (drivers) side has more natural play than the right side as the shaft on the left is just a stub (about 6 inches long) compared with the right side (a foot and a half). However, the play in the video is excessive (if you do a Search above, there are a couple other videos from members who recorded the play in their right side shafts - none were like that).

Unfortunately, it looks like the bearing has come apart and this cannot be replaced at all as the part is not sold separately. (and to replace it, the case must be opened. It cannot be replaced externally as it's behind a lip holding it in.)

• To give you a quick visual, the first photo below is the stub shaft once pulled from the RDM. Note it's very short. It pops into the differential built into the driver's side of the RDM.
• The next photos are from when i replaced my seal (was slow-weeping oil). Note the shaft slots into the RDM's differential 3 or four inches inside the hole.
• The bearings hold the shaft steady. They're internally lubricated by the RDM's oil and the seal keeps the oil in. My guess is that this bearing has come apart.
• Last photos are inside-views of the RDM. Note the spot for the bearing. It can only be mounted/removed from inside the casing. It fits into a slot at the end of the interior of the casing.

Here's what I'd do...

1. I'd pull the stub shaft and see what you're dealing with. Get photos. Is the bearing intact or missing/broken etc. It could even be the differential pinion has somehow come loose etc. Either way, it won't hurt anything at this point.

2. The RDM will need to be pulled to fix it (which means either replace with new or, it might be possible to find a suitable bearing. ) I never really looked into this but if the AD1 has the same casing end, you may be able to find one online used from a wrecked Cherokee and salvage the bearing from it.

3. If replacement is not possible at this time (it's expensive), one option would probably be to remove your propshaft, pull the PTU fuses (I have a list - you'll need to pull 5 of them) and then just drive in 2WD mode (you could leave the driver's axle shaft out at that point if you wanted to) plugging the hole to keep dirt/road debris from entering. The silver "dome" part is a dirt shield.

Sorry, wish I had more optimistic news but it's just the way it is. They don't sell the individual repair parts for inside the RDM or PTU. Hope this info helps though in deciding what to do.

 

Hey @Gremlin11 ,

Is this the issue from March? If so, yes and there's still the oil loss from the physical break on the external part of the casing, you may need a new unit to resolve the leak alone. Either way, let us know what you find. https://www.jeepcherokeeclub.com/posts/3044617/

 

Hi Kathleen,

On our Cherokee's the output shafts can just be pulled from the RDM same as the half shafts without disassembly. They're just held in with a c-clip. Photo below: the driver's side is a stub shaft, the passenger's side is longer. Often the output shafts will come out anyway when pulling the rear half-shafts from the RDM due to rust bonds. :-(

 

Thanks for the info and pics. Being as though the case on the RDM is cracked, I’ll try and replace it. Found one in Ohio. Supposed to be here this week. Haven’t found any vid’s on RDM r&r specifically. I like to pick up a ref manual not only for how-to but torque specs, etc. All Data or Haynes are two that I know of. Anyone prefer one over the other? Also have a 2003 Envoy that either has a clogged pickup tube or shot oil pump. Probably going to wrench on it just because. (Despite a little over 302000 mile, it ran like a sewing machine). So would like reference manual for it as well. Thanks!

 

I have this same problem and the dealer claims PTU is also bad. They quoted 6k to fix it. They claimed the diff had lost all its fluid and the PTU had failed. They said its a common thing that goes bad on the cherokees when people don't service them. Everything I've found says that both the RDM and PTU are sealed for life..... yup the life of 82k miles lol... 2019 Cherokee limited dec23 mine broke.

I got a "service 4x4" light and it made a horrible sound and the car started shaking almost like a warped rotor. It sounded like the "pop can wedged in bicycle tire" sound kids do on their bikes lol. I limped it a mile and had it towed to dealer. They said PTU was shot (just by code. the code was plugged ptu) and RDM to driver side axle loose.

I ordered a replacement from a different dealer and it came damaged. The vent tub was busted off and its pressed in with some sort of sort of sealant. Typical they make this unit non servicable and don't use a threaded fitting. Now im fighting with UPS and the dealer to get a replacment 2k part over a $20 vent tube.

Anyways the rear diff on the driver side had about the same amount of play yours does. I hadn't lost any fluid although the dealer claimed I did. I did find some stardust in it but no big metal chunks or any visible signs of wear on the diff. When I split the diff there was plenty of fluid. Car has 82k miles. Kind of crazy they get away with selling this crap... I've worked with my dad on a few diffs over the years and did one of my own on a ranger. This one looks to be half the size of the ranger diff. Seems undersized for a 3.2l to me lol.

Anyways once I get the diff in we will see if the PTU code clears. I've read where this can throw if the RDM is bad too. I'm hoping because the PTU looks like a nightmare to change. I haven't found any videos or writeups of changing it either. I may make one if I have to change it. It's been on stands in the garage for 3 weeks now.