Leaky diff, bad gas mileage...things...

[B192734]

Hello ladies and gents of the Jeep world. Quick issue here. This has been going on for a while now. My rear differential is very leaky. Fluid everywhere, but I can't see anything leaking from the seal. Enough is coming out that I can get drops on my finger if I touch it. Also it seems like I am getting pretty rotten gas mileage. Originally when I put on the K&N cone and TBS, I was getting around 18-19 mpg. Now it seems like I am just ripping through tanks. To drive the 13 miles to work, it seems like it takes almost 1/8th of a tank. That is horrible if it's true. I am in process of double checking these now as I go through another tank of gas...And on top of this I have noticed that when I put it in reverse especially, it seems to really need me to get into the gas pedal to move. When I let off it seems to want to lug down and just stop right away. Even going forward, it doesn't really want to idle forwards by itself. Wants gas. This just doesn't seem right to me.

Any way that people think that these may all be connected, or totally seperate issues, or totally made up in my head...?

Thanks for any info that you can give.

 

[the1968jeepthing]

i dont know much about cherokees, but it sounds to me like your e-brake might be stuck on... next time you finish driving it somewhere get out and feel the rear wheel, (but be careful not to burn yourself) if it is too hot to touch, your brake is probably partially on. I would suspect e-brake cables. This would give you bad gas mileage, and make it a little sluggish. As for the leak, its probably either the pinion seal or the diff. gasket. clean it all off with degreaser and you should be able to see right where it is leaking from next time you drive it. Also make sure your vent line is not clogged (blow air through it) if it is clogged the increased pressure from the fluid heating up inside the diff. will cause the air (and some fluid) to vent through your pinion seal.

-Brian

 

[B192734]

I'll take a look at the e-brake. I never even thought about that...

As for the diff vent, I looked, and couldn't figure out where it was. I am in the middle of packing right now and don't have access to my Chiltons. Where does it connect? The only lines I saw were the brake lines, so figured I would ask.

 

[buckaroo kid]

Depends but it should be located on top off the diff. Just remember if it's hard to blow into it. It's plugged. Like mentioned before it could be a pinion seal or a diff cover. Put to be on the safe side have you looked at your tranfer case pinion seal? Or even closer to the enigne. But on the other questioned about the e-brake might be engaged you could but the rear of the Jeep on jak stands and then turn your wheels by hand. There should be some resistens but not that much. Good luck and let us know what you find out.

 

[the1968jeepthing]

yes, like buckaroo kid mentioned, it should be on the top of the diff or even coming out the top of an axle tube, or you might have the style that is just vented directly off the axle, with no vent lines, in which case look for a little fitting type deal somewhere in the same location. keep in mind that the actual port going into the axle could be clogged as well, so blow air through both the line (or fitting) and the port in the axle.

 

[B192734]

So, if I don't have an actual vent line coming off, am I supposed to try to blow into it (as in try to blow into the diff)? Would the fitting, if there's no vent line, look like the lube fittings? Or just a little hole? Just not sure what I'm looking for here...

 

[B192734]

Also, one other thought...

When I get under there and look at the e-brake, and find that it IS dragging, what kind of surgery am I looking at to back it off. I've never had to back one off. My cars before always had those auto adjusting brakes that you just pulled up on thhe lever a few times every once in a while and it would take care of itself.

 

[the1968jeepthing]

I was just under my 93 cherokee and the vent tube was on the top of the drivers side axle tube. yours will most likely be there, too. It is very unlikely that you have the little fitting style vent. If you find your e-brake is stuck on you will probably have to replace your cables, because they are most likely seized, or partially seized. It will probably require taking your rear brakes all apart to disconnect the old cables, and reconnecting the new ones. Just do one side at a time so if you can't figure out how it goes back together you can look at the other side.

-Brian