Changing diff lube yourself is easy - Changing differential fluid may not seem like something a novice can do, but in reality it's very easy. Here is what you will ...

Changing differential fluid may not seem like something a novice can do, but in reality it's very easy.

Here is what you will need:
-3 quarts of gear lube (verify capacity of your truck to be sure; mine needed 2.4)
-Differential gasket
-Socket wrench
-Shop rags or paper towels
-Lube pump

How To:
1. Park the truck on a level surface, ensure that it is in Park, and set the brake.

2. Crawl under the truck, and identify the rear differential. It should look similar to this picture:

3. Open the filler plug. NOTE: Some trucks have the filler plug right on the differential cover as seen here, and others have the filler plug on the differential housing itself. Be sure you can open and remove this plug before proceeding! If not, you will not be able to get fluid back into the differential! Mine opens using the end of a socket wrench, with no socket attached.

4. Remove the bolts that hold the cover in place. On my truck, I have 10 bolts. It is helpful to leave one in the top so the cover does not come off until the very end, after the lube has drained. As you loosen the lower bolts, it will begin to leak fluid. After the lower bolts are out, you can lift, or gently pry the cover away from the housing, and the rest of the fluid will drain out.




5. Clean up the cover. I used a little brake cleaner. Be sure to get any metal shavings/residue off of the magnet, and wipe it completely clean.

6. Ensure the gasket fits by lining it up on the cover.

7. Install the cover and gasket. To do this, I tightened the bolts lightly by hand, and then used my socket wrench to tighten them using a star pattern, similar to mounting a tire. It may be best to use a torque wrench, but I applied about as much torque as it took to loosen them. I think it's a reasonable guess; just do not torque them so much that you crush the gasket.

8. Now it's time to fill the differential with new lube. I recommend a high quality synthetic lube, like Amsoil. Using a pump is the easiest way to get the fluid in the differential. The pump shown here is actually designed for a boat's lower unit, but works just fine. Auto stores sell several types of these, as do many places online.

9. Fill the differential until fluid begins to weep out of the filler hole. Replace the filler bolt.
10. Clean up your tools, and take your truck for a test drive!

I recommend watching for any leaks, and checking the fluid level a few days after this procedure, to ensure the gasket seated properly. You did it! Congratulations!

After doing this, I am not sure that I really needed to buy a new gasket. The gasket is rubber, with some type of metal insert. Seems very durable, and looks like it could be reused. I cleaned up the old one, and saved it. Here is a picture of the old one (left) next to the new one:

Also, when you have the cover off and the fluid is draining, note that some old fluid pools on the bottom but does not completely drain. I just kinda scooped it out with my finger:

3+ questions.
1) Your truck is a 2010, what reason did you have to need to change the fluid? Mileage? (I'm at 40k in not quite 2 years) Just a good opportunity to help out someone else?
2) What size are the bolts on your rear differential? (mine is 2009, I suppose it would be the same) Would they be the same for any other years? (other than '07 - present) Would you just suggest grabbing the socket holder? (I'd just wanna know so I wouldn't have to get up and down once or thrice...lol)
3) 1/2 drive for the filler hole?

Seems pretty straight forward and simple, even for part-time DIY'r. Thanks for the How-to!

I have a thing about changing all the fluids early, especially with as much towing I do, and the fact that I wanted to get Amsoil in everything. 10,000 miles may be a bit soon, but I believe in getting fresh fluids in the vehicle after break in. I did the oil at 1,000 miles; differentials at 10,000 miles; and will do transmission shortly. From there on, I follow a normal interval.

Bolt size is 13mm.

Drive is a 3/8 inch.

Thank you, good knowledge there. I don't do any towing, so I guess I should check the manual at some point to find out when I should consider this maintenance.

Thanks for the demonstration, it's good to see that you had ALL the necessary fluids for the job in the photo (Bud Light). How many quarts of that did it take to do the job?

As someone who just changed out the fluid in my rear diff too, I can confirm the fact that this job is SUPER easy.

Other than prevention, what would be the benefits of doing this?

I worked at a Jiffy Lube years ago, and that was one the services we did. Seeing I was the boss there, I trated my crappy F-Explorer very well with fluids. I changed all the gears and trans fluid every few months, just because I could. My Z71 now has just over 80k miles on it, with all original fluids except oil. I've been thinking of doing the trans and gear boxes, but wasn't sure I could do it without the stuff I had in the Jiffy garage...

I'm thinking that the main benefits of changing your diff fluids would be: you're getting rid of a lot of the metal shavings that will be floating around in there, especially if you've never changed them before. Also, if you replace the fluids with top-of-the-line stuff (like AMSOIL), you're probably going to run a little bit cooler. From what I've heard, a transmission's worst enemy is heat, so anything to help is a big bonus.

Cool, thanks. I work on an AF base, and we have an auto-hobby shop with some open bays to rent with tools, for $4/hr. I'm sure they have a lube pump, and anything else I would need. Will go with the Amsoil as recco'd, I know it's a good name anyway.