1995 5-door Jeep Cherokee Country Edition with factory tow package
4WD Automatic with 4.0 inline 6
ABS brakes (don't like them, and the light has burned consistently for 4 years)


Last week, I was camping with my sons scout troop in the southern California hills out by Lake Elsinore. On the way home, we found some mud puddles. Went splashing through the mud a few times and got the XJ completely covered in mud.
Headed back out onto the dirt road and not 10 minutes later, I could hear (and feel) the right, front wheel grinding.

We were up in the mountain roads and in the middle of nowhere with my 11 year old boy and one of his buddies in the backseat. Had to get those boys home. So I limped the XJ down out of the winding, mountain trails to the paved road and headed for the highway at about 15 mph. Grinding horribly the whole way. It sounded like somebody was trying to use one of those old fashioned, hand-operated pencil sharpeners we all had in grade school… 'member those?

By the time I got to the freeway, I could see and smell smoke coming out from under the front of my car. Smoke was coming from the pumpkin and the right side wheel was splashed with oil.

So I had the XJ towed home and started doing some research. Here's what I've learned so far…

1) I hadn't had the axle re-lubed since I took ownership of the jeep 4 years ago. Which was rather stupid in retrospect.

2) Axles have breather vents, just like the engine to allow for oil expansion, and can be a great entrance place for wet, gritty mud.

3) Driving the distance I did on steep and twisty windy roads to get to the highway probably ruined everything inside that Dana 30 axle.


The cheapest option is to go to the local junkyard and grab another Dana 30 off of another Cherokee and do a straight swap. I got a quote at PICK-YOUR-PART for 'bout $100.00. However, it will require some heavy labor to switch the full, Dana 30 axle out.

But, before I do that, I want to take the broken Dana 30 apart this weekend to see what kind of damage I may, or may not, have done. And IF… IF I can determine that the damage is located to say... a blown hub assembly… than maybe I could I get away with just switching out the damaged hub assemblies and their axles with a "new" junkyard set?

I would switch out the hub assemblies and axles as units from the junk donor because I expect that I've super heated my own axles to be dangerously brittle after all the smoke I saw.

I want to avoid having to wrestle with the whole axle housing itself If I can help it.

This of course depends on my inspection of the spider gears in the hub and the seals and bearings inside the housing itself. And If I find metal shavings, I'll have the sense to call time of death for that axle and just go with the full switch.

What do you think? Do you think I toasted the seals and bearings inside the axle housing trying to get the jeep to the freeway? Is there a way I can test them to find out?


David

 

First thing I would do is find out we're the grinding is coming from if it's the diff,it's smoked. If you got lucky it may just be a small rock stuck between the rotor and dust shield, if that's the case drop the diff cover check for any large metal shavings( small dust like metal shavings are normal). If no large metal shaving are found I would just refill the diff and drive it.

Worst comes to worst it's really not that hard to swap and axle just some heavy lifting

 

doubt it was a rock... there was bad smelling smoke wafting out of the differential cover edges.
I'll take a look inside this saturday...

 

okay, After doing LOTS of research, I diss-assembled the dana 30 axle today. First, as per suggestions made on this forum, I grabbed each wheel at 12 and 6 and at 9 and 3... couldn't get either wheel to wobble at all. Sooooo.... I guess that means that the hubs are all right.

Actual removal of the hubs and axles turned out to be very simple. Everything came out nice and easy. I didn't even have to bang on the hubs to get them loose... however, I don't know if that's a good thing or a bad thing.

Removed the diff cover and saw... nothing wrong.



Everything looked good. The oil smelled TERRIBLE tho. Like a cross between burnt peanut butter and natural gas. There were tiny, almost microscopic metal specs in the oil. But I expect that's more from natural wear and tear than any stress. I placed a smear of the oil on a white board for you to take a look. What do you think?




I removed the diff unit from the hub and pulled out one of those orange ring thingies. Thinking it was just an O-ring.


Apparently it had been attached to something.. (bearing?) (race?) (seal?) There is NO mention of it in the chilton manual. Nor could I find it listed as a replacement part at the local parts shop or online. What is it? And is it important? How do I replace it?

So, after diss-assembling the axle and taking a good look...



I don't... know what's going on. Other than the bad smelling oil and that funky little orange o-ring thingie, everything else looks fine. The hubs turn smoothly in my hands with no grating or grinding. The U-joints on the ends of each axle feel smooth as well. The diff gears like fine, and the axles have no worn teeth, galling or score marks at all.

But...But... there was smoke coming out from around the diff cover! And there's oil spray around the inner side of the passenger wheel!

Is it possible that the grinding was coming from the trans-axle or transmission? I don't think so. On the way out of the mountains, I put the xj in neutral and let it coast for a bit. The grinding continued on the right side of the car. So I figured it must be in the wheel or bearings.

I was certain that I had a bad hub over on the right side. But it feels smooth and it passed the wheel tugging test.

If it WAS just a rock jamed between the rotor and dust shield the like jmac108 suggested... that must have been one nasty rock to make the diff smoke like that.

Being new at this, I'm sure I'm missing something important.. What am I missing? And I am worried about that orange thingie... : )

'preciate any advice you all might have. Thanks.

 

its a good guess that some water or contaminants got into your axle either when you were wheeling or before you owned it. if the oil fails it could not provide any lubrication, leading to something overheating and most likely trashing out. if you had smoke coming off anything then you have something being damaged, severely worn, or grooved. and if smoke was coming out of the diff. cover it seriously most likely happened in there or somewhere in the axle shaft. your learning good info. i know not about the "orangey thingey" however i will be following to see if we can help you figure it out. Just keep checking things because your on the right track. and if the oil looks foamy, smells really bad bad, or looks like a milkshake with any kind of serious color swirls in it than it definently contains contaminates I.E. water dirt ect. and they really need changed AT LEAST every 50,000 miles or EVERY time you feel they risked taking in water. which can be overcome by running longer venting tubes usually a rubber hose coming off the top or side of the pumpkin, or pig. also, tie it up somewhere or even run in into the cab if you can find a way. good work man. and may the force be with you...

 

also very nice presentation and post format. kudos

 

orange thing is the pinion seal. And the gear oil always smells that bad. The oil does look pretty bad I would try cleaning it all out with brake cleaner and putting it back together and seeing how it goes. Maybe some of the more experienced guys could weigh in on where to go from here. While you have it taken down this far maybe replace the seal on it they are cheap like 7 dollars on ebay if it looks damaged at all.

 

pretty sure the orange thingie is not a pinion seal but an axle seal. pinion seal is visible on the backside of the axle near the driveline. might need a new bearing kit if your bearings are bad. put new axle seals on while youre at it. slap it together and hope everything's to spec lol. sounds to me like the oil has lost it's viscosity and a bearing or two got cooked. there are bearing on the pinion shaft also that might have gone bad

new axle seals are like 12 bucks for both and i'd recommend replacing them.

 

Its possible your hub is still bad. Its real hard to simulate the weight of the jeep on the hub on a bench test. It happened to my chevy where on the bench it seemed fine but on the road it was terrible. Good luck hope this helps

 

Pinion seal?
No, it's the tube seal, not to be confused with the axle shaft seal and it's not a replaceable part.

To the OP,
If you don't want to replace the entire axle:
A fresh set of bearings and seals are in order. You might want to consider some additional seals for the ends of the tubes if you plan on playing in the mud/water anymore. Like these:


Even if you score a replacement axle from the JY, a fresh set of seals (shaft seals and pinion seal) should be installed at the very least.

 

Hey, you guys are great! Your comments have lead me into considering options and causes that had previously never occurred to me.

'appreciate it.

The orange o-ring thingie...
According to general consensus out there in the digital ether, the orange o-ring is extra silicon sealant that has squeazed out around the axle housing tube ends as they were pressed into the pumpkin housing at the factory.

http://www.jeepforum.com/forum/f9/da...r-seal-520946/

http://www.jeepsunlimited.com/forums...d.php?t=531209

http://www.naxja.org/forum/showthread.php?t=1061058

...and since everyone seems to be using this fellows picture.. heres a link to his axle build.

http://www.stu-offroad.com/axle/d30seals/seal-1.htm

There is no replacement for that o-ring of left-over factory goo. But, apparently, neither is it needed really. Most people just put in a smear of their own silicon where the goo-ring used to be and so far, every ones been fine.

Okay, good, so forget the orange goo ring. I'll put in a smear of RTV and move on.

The hubs, axle shafts, and diff all came out easy... (I know, I was lucky.) And the inner axle seals aren't warped, nicked, cracked, hardened or damaged in any way that I can see. So, I think I'll just slap the Dana 30 back together this week with fresh oil and diff cover seal. Just to see what happens. If the grinding continues, I'll take it from there, and start replacing bearings and seals. I'll report what happens....

David

 

Also, one thing I don't think was pointed out is the possibility that your vent tube may be clogged. The only way to have oil splashed on your wheel is to have oil ejected from the differential down your axle tube. Two things can cause this, a faulty seal or pressurizing the pumpkin. You said that your seals were in good shape so that would leave me to believe that your vent tube is clogged causing the oil to push past the seal. Maybe not the rubber vent tube itself, but the outlet of the diff. How that could have happened I have no idea... Just throwing it out there.

And if you had "smoke coming from the pumpkin" was it coming off the outside of the pumpkin? You just ran through a bunch of mud, which could be getting burned off the extremely hot pumpkin, OR your diff cover seal failed causing most of the fluid to drain out, causing you to overheat. How much fluid did you get out when you drained it at home?

If it were me, I would replace the bearings. You may get away with not replacing them for the short term. But if they overheated and caused your diff to smoke they won't last too much longer.

 

I think your smoking.pumpkin is due in large part to sometging rather simple: you put your axle through water and mud, the mud as an aggrogate and the water as a displacement for the oil, could cauae this scenario : (keep in mind this is all hypothosis in my mind)
Water and mud enter axle
Mud strips gears of oil, water boils from resulting friction
Steam pressurizes the now clogged vent tube.untill the.axle seal fails, causing your.soaked tire. As for the grinding sound, id.bet you just had aggrogate in the axle tub or maybe even the.diff. Remember, they have just about a pressed in fitting for clearances, so any foreign aggrogate or debris could cause all sorts of ruckus.

Just my 2¢

 

Yup. Very possible scenario.

 

try swapping the hubs from left to right and vice versa, see if the grinding sound moves too...or simply disappears with this teardown/rebuild. As pointed out earlier, make sure your diff vent tube is not clogged. Maybe I missed it, but I didnt see anything reporting the condition of the vent tube...was it even attached?