Changing differential fluid - A step by step "HOW TO"

I did this today, 25,000 miles. The oil looked like it was due for a change. I did not have a 24mm socket so I used a 15/16 6 point. Worked great. Other than that, I dropped the spare tire to make sure I had enough room to put the new oil in.

 

What if the front differential only took .75 qt of oil and wont accept any more?

 

Looking to do this soon

 

Is it possible to over fill the rear differential? I have a 2015 Tacoma TRD Sport DCLB Pre-run 2x4. I removed a total of just over 3qts, and added back almost 4 qts. Truck was on level ground. I filled until I saw a little start to run out of the fill hole. The level looks to be right up to the fill hole. Should I remove some? Or just drive it and see how she responds?

I used

$30 Mobil 1 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

Mobil 1 75w-90 synthetic gear lube. No additive as my truck doesn’t need it.

New to TW. And I appreciate all the info on here and the tutorials on DIY maintenance. Thanks for all the help.

 

Welcome to TW!

It is possible to over-fill the rear differential, but not by following the method you describe. According to pg 528 of your Owner's Manual, your rear diff is 3.66qts. May have been a little low before you drained it and, depending on your definition of "almost 4 qts," it sounds like you're good to go. FWIW, I see no need to remove any.

 

I believe the manual says “2wd except for prerunner” 3.66qts “4wd and prerunner” 3.12qts.

I have a TRD sport prerunner. So I should have put 3.12. But it didn’t start to leak out until 3.5qts. I replaced fill plug and allowed the fluid to move into axle shafts. Then removed full plug and added a little more. I have about 2/10th of a qt left. So I added around 3.8-4qts. I’m a little confused. I took for a test drive. Seemed fine. Checked level again, no fluid came out. Level seems right below fill plug hole. I’m gonna just call it good. But wanted to make sure I didn’t add a whole qt more then I needed and cause any issues.

Thank you for the help.

 

You are correct. The process you used was also correct. IMO, however, you are good to go and I still see no need to remove any.

 

Just finished up with the front/rear diff and xcase.. Not that hard.. good write up thank you!! I was fulling expecting to see at least one metal flake in there some where and all I saw on the magnet was "goop"..

 

I got 1999 taco by 3.4l rear wheel drive. Does the dif take LSD? I dont think its ever been done. There no tag or sticker on dif.

 

That's rear differential

 

According to pp 237-238 of your Owner's Manual, your Front and Rear Diffs both call for 80W-90 Hypoid Gear Oil API GL−5. LSD additive is not required.

 

Thanks but when I jack the rear up and turned the wheel they went opposite direction. Is that what lsd is used for? I dont know .just got a 1999 Tacoma v6 3.4. L 2 wheel drive

 

Do you know where to download the service manual Norton?

 

https://youtu.be/duLUwp11i5A

 

Maybe I didn't understand your original question correctly. I though you wanted to know whether you need to put LSD additive (aka friction modifier) in your Rear Diff, not what the purpose of an LSD is. @Yota_Ivan kindly answered the latter question. Your Owner's Manual does NOT specify LSD additive for your truck. FWIW, it's not specified for my son's '01, wasn't specified for my '04, and isn't specified for my '13, so the answer has been pretty consistent.

From the Toyota Owners web site. You may need to create an account, which is free, to access the direct link I provided above and in my previous post...

 

I do appreciate all the help. I just dont want to screw up this jem. 1998 by 3.4l extra cab rear wheel drive

 

Liters

 

Changed out the gear oil with 60K miles on the clock... the rear diff plug had a few specs of debris adhered to it and the oil wasn't all the bad (dark but no water evident/no burnt smell). Transfer case gear oil looked like new and the front diff gear oil was similar to the rear. A few squirts of Liquid Wrench a few days ago on the fittings, a 6 PT 24mm socket, a T55 star bit and new washers made the job go very quickly.
I went with AMSOIL's "Easy Pak" in 75w90 for the 3 diffs. No pump needed as the "EasyPak" container is a like a kid's squeezable juice box.
No fuss, no muss, no spills, no waste AND NO MESS!!! Total job took including "clean up and put away" took about 1.25hrs.
Thanks to the OP and the others for the great write-ups!