Changing the diff. oil early (the first time since new) is debatable.
Some people NEVER change theirs, and never have a problem.
I changed mine at about 3,000 miles because I wanted to get out the metal from the new gears, and wanted to change to synthetic.
It is fairly cheap to do it yourself. Having the dealer do it and charge so much is what makes one question if it is really necessary.
You would have been OK to tell the dealer to wait 'til you had the recommended mileage on the Jeep. However, your Jeep is better off for having the first change done early.

 

got 198,000 on my last Jeep with NO fluid change on the differentials. The fluid will go forever if it is not contaminated by moisture. The recommended fluid change interval is a good service department work-maker. Back in the olden days of rear-wheel drive and non-synthetic lubes nobody changed diff oil, only added to it. I personally will not change mine unless repair is needed which necessitates pulling the cover.My opinion and practice only, you all do what you feel is best....

 

I wouldn't pay a dealer to do it, but was glad that I changed mine at 7k.

Front diff

 

The only time I changed diff oil in my cj's was when it flooded here and I got water in my diff, and one time when I went muddin before extending my breather lines. Changed the jk's at 15,000 and also last weekend after my new gear break in. Don't plan on changing for a long time unless in water above my diff breathers.

 

that color of your fluid is from water in your axle, have you been in water deeper then the top of your shock tower where the breather hose is?

 

where exactly is this breather tube?

 

https://www.jk-forum.com/forums/jk-write-ups-39/breather-tubes-extended-46802/

check that out, the front breather tube comes up to the top of the drivers side shock tower from the diff, the rear is on the passenger side I forget where exactly somewhere by the frame i think.

 

Your dealer is on crack. Unless you wheel in water a lot, you shouldn't even need to change it at 15K. I plan to CHECK mine at 50K when I do the trans service, but if it looks good, screw it.

 

Redneck is right, but I'll toss this little morsel for thought in,

Ford, for example says to NEVER change the rear end fluid on 97 and up f-150 trucks. Its synthetic fill from the factory. If you DONT have a magnetic plug or mag in the cover and wheel hard(Dana 35 owners can testify to this even tho its a crap diff to start with) the possibility of problems goes up, BUT is not gaurenteed.

Really fellas its cheap cheap insurance, if you USE your Jeep. Dont assume that your Dana 30 built by the new guy at Dana will be as good as the one built by the guy whose done it 1000 times.

Different batches of steel, revisions in the heat treating process's, changes in steel suppliers for the bearings all attest to this.

Signifigantly larger tires and wheels add the stress on those parts, they werent designed for.

Manufacturers tolerences. We all know substandard crap can and does leave the assembly line on a regular basis.

Not mechanically inclined to change it yourself? Thats ok, smaller shops can do it usually at less than half the price of the stealership.

Just my 2 cent.

 

hmm ive got 2500 miles to go till i reach my first 3k miles, i might do this just to clean out any metalic pieces from break in then do it again at 15k. Any suggestions on which brand to use?