Why don't you check the fluid?

My rear diff had next to no fluid, luckily there was no metal shavings. I only used to hear a slight howl.

 

how do you check it? Do you just open up the plug and look w/ a flashlight? The level of the fluid should be near the plug right?

 

Yes it should be dead even with the bottom of the plug hole.

-If it's low, put more in.
-If it's really low, take off the cover and inspect for damage. (metal shavings maybe chunks if it's really, really low)

-If it spills out over the hole that means 1 of 2 things.
1. someone filled it when the front end was on ramps
-or-
2. You have a bad seal or broken/cracked vent tube and you've taken on water.
Either way, if it's over filled, you should change the fluid to be safe.

 

Is it possible to change or add differential fluid without taking the whole cover and axle off?

 

Yes it is. You have to get the "sucker gun". It looks like a grease gun with a hose. I got mine at auto zone, around $10.00. Stuff the hose in the fill hole on your diff and pull the plunger on the gun. Works well for refilling too.

 

If you mean the axle cover, not axle and/or cover. No need to remove the axle:laugh:

Add= Yes
Change= No
In order to change it, you have to take off the cover to drain the diff, and while your in there inspect the inner workings for wear. Do you have a Haynes manual? If not get one. Most general maintanence is covered in there.

 

on my way to check it out

 

Well, there is this funky grinding clunking sound that i have in my jeep that feels like it is right under my feet. It only happens when I drive slow.

Is it my diff low on fluid? Or could it be a bearing? And what diff fluid is best with an open dana 30?

appreciate it

Grinding and clunking noises are unlikely to be coming from your differential unless there are some very very serious issues going on in there. The noise is probably some other lovely Jeep feature (track bar, control arms, motor mounts, bar pins, etc). You can check the level at the differential plug, as said above, by just removing it and see if fluid is right at the level with the plug. You don't have to remove the cover to check it, and you actually don't have to remove the cover to change it either. If you want to change it, you can buy a hand crank vacuum pump or get an electric/pneumatic one and remove the fluid that way. When you get to the bottom where little fluid is left, add some of the new fluid and then remove that also before filling it all the way up with the new fluid. This way you remove just about all of your old fluid and you don't have to remove the differential cover. Removing your differential cover is a good thing to learn, though. It just involves unbolting the cover, cleaning/draining it out, making a new gasket, and filling it back up again. It's your choice. Hopefully that noise really isn't coming from your Dana 30. Good luck!

 

hey, i don't think it is the diff, but knowing that it was coming from that area, that was just my idea. I know how to do the deed of changing the fluid, it's just that I was trying to figure it out before i fork over the money on fluid.

 

Check the ujoints on your rear shaft. Just had a similar problem with my Dodge and it ended up being the ujoint on the end of the rear shaft that connects to the rear yoke. Vibes will travel up and rattle the t-case, which makes you feel it right underneath you.

 

I have the same issue.
Replaced front DS (totally shot), and front axle u joints.

thanks beachin, ill check the rear DS next, i think those are the only u-joints left for me to replace.

Ill post back if i find the culprit, and post up if you find yours 99greenmachine!

Almost forgot...my tranny mount is completely gone, replacing next week, so ill let you know if that helps me.

Ben