• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Rear differential oil ?

BoostN

BoostN

Well-Known Member
Staff member
Administrator
Messages
8,704
Reaction score
1,552
Location
Tennessee
What oil are you guys using in your Differential. I've never changed mine since new. I have around 37,000 miles on the truck right now. Good weekend project this sounds like.
 
I just changed mine over to amsoil. I added some of the slip lock when I did it just to prevent possible chatter. I recently heard we arent supposed to use the slip lock but I dont have confirmation yet. gonna do the front diff as soon as I get a manual pump to fill it,
 
tinman22 said:
I just changed mine over to amsoil. I added some of the slip lock when I did it just to prevent possible chatter. I recently heard we arent supposed to use the slip lock but I dont have confirmation yet. gonna do the front diff as soon as I get a manual pump to fill it,
Click to expand...

Do you have the locking diff? I don't think the amsoil gear oil has the additive in it already so if you do have the locker i would add the sliplock. Normal GL5 fluid has the additive already in it.
 
I wouldn't touch it till atleast 100k. I may not ever change mine. Personally i wouldn't worry about it unless there's a possibility of water or other contamination. Just keep a check on the level of the fluid. The oil isn't gonna break down like engine oil or transmission fluid because there isn't the extreme temperatures infuenced upon it in the differential. Some people just like to change it though. i just think its a waste of money. just my $.02
 
yes. I shodl have the G80 gov lock in there. thats why I Added the slip lock. the front dif shouldnt require any additive though,
 
it smells like grape juice. I Was plesantly surprised by the odor when I drained the old fluid out.
 
havent even thought about changing mine yet. Ill probably go to amsooil though.
 
If memory serves me right, (sometimes it doesn't) I think the manual advises to change after 500 or 5000 miles to remove break in material. After that you're good for 100K.
 
Agreed, it's best to change the rear at 5k and then you should be good to 50k or more intervals. I did both front and rear early (2k) and put 75w90 Mobil 1 in. As long as it's good synthetic you're fine. I did both with grape juice on my '05 but at $28 per for 6 qts, I liked the M1 price at Farm & Fleet better when it came to the '06.
 
I changed mine at 10,000 and it was pretty nasty. Refilled with Mobil 1 75W-90 Synthetic so far so good.
 
Highly recommend you change that oil. Both front and rear 75w90 (front), 75w110-75-140 Amsoil, Mobile 1, Royal Purple are all fine in the rear diff. You are probably 1.5 quarts low too. I would change it ASAP.
 
I switched over to Mobil 1 at 500 miles. The factory stuff stinks bad. I also had slivers of metal on the plug/magnet too. Glad to get the crap out early.
 
That makes me feel good. I guess i'm going to have to find some time to change mine...:D
 
You must log in or register to reply here.
Back
Top