Differential fluid flush
 

Hey guys, Just picked up a J30 diff. How do I "flush" the diff out and how much do I fill 'er up to? This is my first time doing this... ever. No seriously... it is...

LOL Thanks for any help!

There is a drain plug on the bottom of the differential cover. Open that plug with the differential over a drain pan. Allow all the fluid to drain. Reinstall the drain plug.

There is a fill plug higher up on the diff cover. Remove the plug. Place the diff on a level surface and pour the 80W-90 fluid of your choice into this hole. The fluid does not need to be specifically for limited slip differentials, since the VLSD is a sealed unit. Fill the diff until the fluid level is even with the fill hole. This is why it is important for the diff to be on a level surface. Once full, reinstall the fill plug and you're done! Simple!

Nice write up! THANKS!

I should be getting this diff in my car this weekend if all goes well.

No Problem! Let us know how it turns out... :bigok:

Hopefully I'll have this done and installed in my 14 by Saturday afternoon. loading it up and headed to my cousin's shop in the morning to use a lift!

http://www.bumnah.com/repair/IMG_7336.jpg

a picture of the drain (bottom) and fill (top left) plugs

Thanks Bumnah, I've never done a diff fluid change before (never kept a car long enough LOL) But yeah, this helps out a lot!

when i bought my j30 diff i flushed it with 5-30 weight oil at the shop i just pumped in oil till it came out clear took like 12 quarts lol. i drained it put the drain plug back on.

i filled my diff on the car but thats cause i had a lift anyway just put 80-90 gear oil in the fill plug untill a little leaks out from the fill plug then it has enough mine took like 1.5 quarts.

when my SR goes back in im using Royal Purple 75-90 gear oil in my tranny and diff so ill tell you how it feels... i hope it actually is better not just snake oil cause it was $10 a damn quart lol

pickup a cheap pump from harbor freight. makes life a lot easier I ran a long pipe and slowly drained fluid into the diff when i first did it. what a ****ty experience that was. i bought a $5 harbor freight pump made the job 50 times easier and faster.

AZ has a proper pump for around $6 and is proper to do the job has fitments for the bottle of fluid so u don't even have to use any adpator.
I just chenged on my car yesterday.