That aside, servicing the differential is pretty easy.  Place an oil change pan under front differential.  Remove the bolts leaving a couple loose but still intact (usually just one at the top loosened about halfway works.  That prevents all the oil from gushing all over the place.

Take a rubber hammer (available at any hardware store) and give it a few taps and it should come loose and the fluid will of course drain. Scrape the gasket material off the inside of the cover and the diff housing mating surfaces.

Once that's done, some folks take a can of brake cleaner and spray off the gears and internals if there's gunk built up.  Make sure the chemicals drain and are dry before replacing diff cover.

Some guys use gasket maker, I just used the gasket from Napa (which sold me a dana gasket, so you know it'll fit since they made the axle), and with a little finessing got it back together and all of the bolts snug- not super tight.

Then I removed the fill plug (it's rubber so just use a flat screwdriver to remove) and fill with quality gear oil until it's level with the hole.  Reinstall plug.

That's how I serviced the Dana 35 in the back of my Jeep.

And the bad name the dana 30 front and dana 35 rear axles get is from the guys that run bigger tires and more power and put a lot more stress on the axles.  They are adequate for normal use and some trails and about 33" tires max, so they're not overly strong, but if you just use your jeep as a daily driver, they will hold up for the life of the vehicle.

EDIT:
For future reference and to save some $$, check this out.
click me
to make oil changes easier yet (gives you more room to remove oil filter)
click me
Just don't use a fram filter.  Baldwin, Hastings, Wix (napa), or Purolator are good.

-- Edited by ChevelleSSLS6 at 00:24, 2009-02-23

I went and bought the roll of gasket material myself cut out the gasket, drained out the fluid replaced with mobil that was 45,000 ago , I saved myself $35 dollars, and $72 for labor ,I have stock 8.25 rear, Dana 30 front, I am running 33x9.5x15 on stock rims, the diff fluid breaks down after 50,000 miles. Offroading rigs (30,000 miles)I was wondering if this was true, Adam?

I forgot to mention most quickie lubes (I worked at a dealer in 'the oil pit' and they do this!!!) is they suction the old fluid out, and refill.

This sounds good and fast at first until you consider that there's quite a bit of residue left up in the gears and whatnot, and the suction line likely isn't at the very bottom of the diff. So, it's like paying full price and getting 3/4 of an oil change.

This could be why it's dark already.

-- Edited by ChevelleSSLS6 at 11:16, 2009-02-23

Question I have...is a LubeLocker gasket reusable?