Jeep JK Wrangler Maintenance
Differential Fluid Change Write-Up

March 05th, 2008 | Category: Jeep JK Write-Ups, Operation & Maintenance

Changing the fluid in your Jeep JK Wrangler’s differentials is an important part of routine maintenance. New gear oil will insure your differentials will be properly lubricated and functioning properly. And, unlike previous Jeep Wranglers, you will not need to pop open the differential cover in order to perform this maintenance. Granted, I do recommend that you do so anyway from time to time (every other fluid change) as it will give you a chance to inspect the gears within it for any damage or unsual wear.

Following "Schedule B" in the Jeep owner manual (heavy driving), I change my differential fluids every 15,000 miles. However, It’s always a good idea to do this after submerging your axles in deep water for prolonged periods of time as well. Below is a list of what you will need and instructions on how to perform this service yourself on a Jeep JK Wrangler Dana 30, or Dana 44.

What You Will Need


• 3/8" Drive Ratchet
• Torque Wrench
• 3" Ratchet Extension
• Oil Catch Pan
• Paper Towels

What You Will Need
to Get for this Job


(4) Quarts 75W90
Synthetic Gear Oil*

Front Differential Capacity:
2.7 pints (1.35 quarts)

Rear Differential Capacity:
4.75 pints (2.375 quarts)

* NOTE: I personally like to use Royal Purple Gear Oil but have also used Mobil 1 and Valvoline Synthethic with good results. If you have a limited slip differential (LSD), you WILL NOT need to get any friction modifier as good synthetic gear oils will already have what you need in it.
   

Basic Fluid Change Instructions

1. Using the square head of a 3/8" Drive ratchet, remove the fill bolt from your Jeep JK Wrangler’s differential cover. 2. Place an oil catch pan underneath your Jeep JK Wrangler’s differential. Then, using a 3/8" drive ratchet with a 3" extension attached to it, remove the drain bolt from the base of it as shown in this pic. 3. Allow your Jeep JK Wrangler’s differential to drain completely before proceeding.
4. Your Jeep JK Wrangler’s drain bolt is magnetic and the inside end of it should be fuzzy with fine iron filings. Use a paper towel and some brake cleaner to wipe the bolt clean.
5. Using a 3/8" drive ratchet with a 3" extension attached to it, reinstall your Jeep JK Wrangler’s drain bolt back on to the base of your differential as shown in this pic. Tighten this bolt to 25 ft. lbs. of torque.
6. Fill up your Jeep JK Wrangler’s differential with SAE 75W-90 synthetic gear oil. The Front differential only needs 2.7 pints (1.35 quarts) and the rear only needs 4.75 pints (2.375 quarts). If you have factory covers, all you need to do is fill up your differentials until gear oil oozes out of the fill hole. If you have an after market differential cover that has a higher fill hole (like a SOLID or ARB), DO NOT be tempted to fill up your differential with any more gear oil than it needs as it will just end up getting pumped out of the breather tube and make a big stinking mess.
7. Using the square head of a 3/8" Drive ratchet, re-install the fill bolt on to the differential cover of your Jeep JK Wrangler. Tighten this bolt to 25 ft. lbs. of torque.

Thorough Fluid Change Instructions


In order to perform a thorough differential fluid change, you will need to pull your differential covers off of your Jeep JK Wrangler’s axles. For instructions on how to do this, click on the Jeep JK Wrangler SOLID Differential Cover Installation link below as it will cover all the steps you need to follow in order to do this. Of course, if you do not have aftermarket differential covers, all you need to do is follow this write-up with the only difference being that you will be reinstalling your factory covers:

Jeep JK Wrangler SOLID
Differential Cover Installation

That’s it! Please let me know if you have any questions and don’t forget to take your old gear oil to your local recycling center (PepBoys, Autozone or the like).
 

10 Comments so far

  1. JKTyrant March 5th, 2008 8:01 pm

    DO NOT be tempted to fill up your differential with any more gear oil than it needs as it will just end up getting pumped out of the breather tube and make a big stinking mess.

    Lol I did this filling up the front diff =) Funny thing was the stinking left it made was in my friends driveway =)

  2. coyot'e March 6th, 2008 1:20 pm

    You the Man Eddie. :) thanks

  3. coyot'e March 6th, 2008 1:21 pm

    Also any thoughts on Amsoil products from anybody?

  4. wayoflife March 7th, 2008 10:47 am

    Amsoil products are great :)

  5. javier March 9th, 2008 3:52 am

    Dana 30
    Dana 44
    it´s the same quantity ?

  6. wayoflife March 9th, 2008 10:52 am

    The Dana 30 is what you will have as a front axle if you have an X or Sahara. A Dana 44 is what you will have as a rear axle on all but a handfull of 2-Door JK’s made in early 2006. Rubicon’s will have Dana 44 front and rear axles and they are a stronger.

    Eddie

  7. Bo March 12th, 2008 11:09 pm

    Just did this…Great write up. Its sooo easy to do, i will never have anybody do this for me again :)

    Thanks

  8. Jim March 30th, 2008 10:11 am

    I just did this and I didn’t need as much oil as was listed. I filled until it came out the fill hole but only had about 1qt for the front and about 2 for the rear. Has anyone else noticed this? Just want to make sure that I put enough in there.

    Thanks for the info.

    Jim

  9. wayoflife March 31st, 2008 11:20 am

    Hi Jim, with factory diff covers, this would be correct and you have the exact amount that you need in. :)

    Eddie

  10. Wes April 1st, 2008 4:55 pm

    yup, i just finished mine on my 07 2 Door. required about 1 qt on front and 2 qt on rear. :)

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