Had my oil changed today at 20,000 miles (08 Unlimited). The shop said that my rear diff fluid is very dark and showed it to me, They indicared that it should be the color of hoiney. (It is a dark grey, almost black) Should I be concerned? I will take it into the dealer as it of course is still under warranty. My driving is all highway driving.
Thanks for any help.

 

I had a quick lube shop try and tell me mine needed changing at 5000 miles because it was dark. Apparently (according to dealer tech) Jeep uses an additive that makes the gear oil look darker than the quick shops are used to seeing. I had the dealer service both axles at 18000 miles since both diffs were starting to weep a bit. Drained, pulled covers, checked gears, resealed. No abnormal wear. Based on the cost of the Jeep fluids they must use NASA shit!

 

Thanks for the reply, much appreciated.

 

Ok guys here goes the latest diff hint. For all new jks i would change diff fluids at 6,000 no later when your jk is new. After that you may be able to go longer, but check the fluid by removing the fill plug and checking the color smell and texture. If it looks like honey your cool, if it is black change it right away.

Use a 75 weight synthetic. This may help you w/warranty issues later. It is what the dealer uses in the shop.

I just opened mine (11,000/mi) at the dealer and holy $&&( it was jet black and thin, this is not good:(

my locker is also toast.

Good news. Do this yourself do not bother paying the dealer. On these diffs there is a drain plug and a fill plug (d44). That makes this a 20 min job max.

Drain and chek the fluid for metal. Replace the drain plug use thread seal. The diff fluid will come with a pump on top of the container. Put the nozle in the fill hole (top) and fill til you see the fluid drizzle out the fill hole.

My manual says to repalce diff fluid at 36,000 miles, that would have been a disaster, and my diff would have gone way before that.

My front was fine, but replace them at the same time, you already bought the fluid it is an extra 10 min.

Do not delay it is a small investment, and by the way record when you did the fluid change and save receipts. If you do not keep records they will not honor your warranty, and this has already cost me 1800.00 on my wifes grand cherokee.

An ounce of prevention is worth a diff.

 

My rear diff fluid at 3,600 miles:


Didn't take a picture of the front - it looked fine.

 

That's about how mine looked at 2,500 miles. I replaced front and rear with Royal Purple 75-90 and will probaby not service again until 15K.

 

About the same here but did the change at 4500 miles.

 

wow I didnt know this needs to be changed so early. i had mine at the dealer the other week and they said I need to change the diff fluid since I am around 15k miles.

Question:

Is changing the diff fluid covered under warranty? The dealer said it wasnt but I ask again since one of you said it was covered. Maybe you bought an extra service plan?

...if it isnt covered under warranty I am gonna figure it out myself because they wanted to charge around $150.

Another Question:

How regularly should this be changed? ...every X miles? and how does wheeling effect this?

Sorry for all the questions!!

 

Did you change it at 15K miles per the maintenance schedule? If not you were over-due anyways.

 

The diff fluid is not covered under warranty, just like engine oil isn't covered under warranty. They charge $150 because I believe they actually remove the covers and do it right, and that takes a little more time (at the high hourly rate for a dealer). The maintenance schedule says every 15K miles, but if you off-road, especially in water and mud you'll want to do it more frequently, immediately if contaminated. You can do it the easy way though and just drain and re-fill.

When I did mine (@ 15K) it didn't look nearly as bad as some of the others have posted.