Brett2424

I'm working on a '97 Cherokee with an NP231 Transfer Case.
This noise was hard to capture perfectly. It sounds like the chain relaxing against the aluminum case (though it wasn't the chain). It also kind of sounds like a really sloppy roller bearing.
Is this normal noise?
When in use, I notice no odd noises from the transfer case. Also the shaft does not seem to have any odd play in it.
I was turning the shaft by hand with the transmission in neutral, and the 4WD disengaged.

agreen

Can't tell from the video. You'll have some noise inherently, but the best way to tell is with the vehicle in park, 4H, and the front shaft removed. If the front pinion moves more than about 1/4" either direction, the chain has enough wear to warrant a change. Bearing noise will be apparent when driving. Otherwise, it's probably fine.

tech

To me it sounds like the chain is jumping around because of they way you are turning the shaft . Did it make noise when it was in the jeep ? but it could be the chain is a little loose .

Brett2424

I'll try to wiggle the pinion around today. I had planned on replacing the u-joints in both shafts, so I'll have the front one off anyway.
This is my wife's daily driver. She reported that there is no unusual noise when driving. She's usually pretty good about noticing new noises if they develop suddenly, but I'm not sure that she would notice a noise that grew gradually.
I was going to replace the leaking rear seal, and replace u-joints, as they have about 280,000 miles on them. I didn't think to road check it before putting it in my shop.
I was mistaken about play in the shaft. I'll post a video showing what I found.

Brett2424

I'm pretty sure that it is not the chain making the noise, as the chain isn't moving at all in the video, but the noise is present. I did notice that the noise doesn't happen if I turn the shaft slowly. When I turn it faster it sounds kind of like the *****, or rollers, (I don't know what kind of bearing is at the front of the shaft), are flying out a bit, and then settling into place again when I stop turning.

Brett2424

I had checked the shaft for play prior to taking the rear housing off, and didn't notice any.
Now, with that housing off, it seems to have a lot of play. This is my first time digging into a transfer case, but I'm guessing that it should not slop around like in the video that I've attached to this post. Am I correct?
Fluid changes are the only maintenance that the transfer case has received. It now has about 280,000 miles on it.
It ran a bit low on fluid recently, before I noticed that the rear seal was leaking.
What I'm thinking right now is that, given the miles on it, it might make sense to rebuild it.
I'm having trouble finding a rebuild kit that lists which brand of bearings are included.
I'd appreciate thoughts on my notion of rebuilding the transfer case, and also on where to get a good rebuild kit.

agreen

Damn you got me.

Ok, so here's the deal with that. That rear housing has the rear bearing in it. I didn't even notice that you had it off in the last video. I had my phone up to my ear. Put that thing back together with some gray permatex right stuff, and make sure your oil pump pickup tube doesn't fall out of the oil pump. On another note (and I may have missed it) WTF are you doing with that off?

Brett2424

That made me laugh. It's a fair question. I took it off because I need to replace it. The lip where the seal goes had a chunk out of it (enough to allow fluid to leak out). The break is most likely due to my tool slipping when I was trying to get the dust shield off (the thing behind the rear seal). I've seen that part referred to as an "oil slinger", though there should not be oil out where it is located.
With the rear housing, and its bearing, in place, the weird noise that I posted about originally is just a noticeable. I first noticed the noise when when the rear housing was in place.
Are you suggesting that I shouldn't be concerned about the noise?

Brett2424

That made me laugh. It's a fair question. I took it off because I need to replace it. The lip where the seal goes had a chunk out of it (enough to allow fluid to leak out). The break is most likely due to my tool slipping when I was trying to get the dust shield off (the thing behind the rear seal). I've seen that part referred to as an "oil slinger", though there should not be oil out where it is located.
With the rear housing, and its bearing, in place, the weird noise that I posted about originally is just a noticeable. I first noticed the noise when when the rear housing was in place.
Are you suggesting that I shouldn't be concerned about the noise?

Brett2424

This is my third attempt at responding to this. The previous two were held for review by a moderator. I don't know why they were flagged, and the reviews apparently never actually happen.

I took the rear housing off because it was damaged and I needed to replace it.

But, with the rear housing, and its bearing, in place, the weird noise that I posted about originally is just a noticeable. I first noticed the noise when the only thing that was off was the driveline.