2004 LS rear diff, I need to service. Hate to sound dumb, but is the large (1 1/4- 1 1/2") threaded plug on the rear cover the drain plug, or does cover have to come off? Plug requires a 3/4" drive to remove.
Thanks for any help

 

the cover needs to come off.

even if there is a drain with a lsd its a good idea to take the cover off and clean out all the clutch material.

make sure you use lsd specific fluid and a friction modifier.

use rtv sillycone to seal it up just let it dry a few hours before refilling.

the plug at the halfway mark is the fill plug it generally has to be 3/16 below the plug when filling dont worry about it if you put a bit too much.

 

I recently did mine and removed the 3/4" plug only. It's running fine.

What method do you recommend to clean off the clutch packs?

 

Make sure you can get the fill plug out before draining the differential via either method.

-Rod

 

To pull the cover on a 3rd gen with independent rear suspension, the whole pumpkin assembly has to come out, that is why they put a drain plug on the cover. Like shorod said, make sure the fill plug comes out before draining. I have done my mountaineer like this a few times and have had no trouble.

 

you dont take the cover off on the 2002- and newer. the amunimum case is bolted to the body with independant rear suspension.. thats why you got the big plug. take it out and drain the oil. take out the smaller plug to blow thru or flush. Reinstall the big plug, then fill thru the smaller plug till its full to that point. 75 w 140 full synthetic with a bottle of friction modifier from Auto Zone.

 

I have a 2003. I took off the fill plug (Smaller Plug) and fluid started coming out. Is this right? Is it overfilled? It was on a level surface.

The fluid was pretty dark. Am I due for change? It has 90K miles on it.

 

Im getting ready to change rear diff oil in mine. Got a 2004 explorer 4.0 4x4. with 74k miles.

 

Dealer suggested to me that I change the fluid every 40k. It does come out very dark, I guess from the clutch pacs.

 

big plug has maybe a 3/4 inch drive and 1 inch thread or bigger... that is the drain. half way up the side is a smaller plug with 3/8 drive i think... that is the fill, should come up to the bottom of that plug. Not a good setup to flush or clean,, just drain, let it set for 15 minutes, reinstall BIG plug and refill. Should be 75 w 140 gear lube. full synthetic is best. If you have any gear whine, you might add a bottle of the friction modifier and see if the change in viscosity helps..(this is a must if you have limit slip clutch).