Differential Fluid Change Simple Question

[Dgerre1]

I think it's about time to change the rear diff fluid in my 04 4X4. I'm guessing this is pretty straight forward. Any suggestions on what I should use? I drive mostly around town and off road a small bit for hunting/fun . Any tips or things I should consider?

Also, should I do the front diff while I'm at it? Any differences?

[Tundradrenalin]

See link: DIY: Differential Oil Drain & Fill

Also, do a little research in the Drivetrain forum. You'll see the debate on diff oil is similar to the crankcase oil debate. Your manual states SAE w90. And if you have LSD, you'll need to read the labels a bit more for the right additives. But regarding oil weight, 75-w90 will do you right, and is a fairly easy find at most auto parts stores.

Please check out some other threads, this topic has been discussed many times. Not putting you down, just saying, the answers are out there.
THANKS!

[tinik]

Originally Posted by Tundradrenalin

And if you have LSD, you'll need to read the labels a bit more for the right additives.

in some cases look at your diff and make sure

[HOGWILD]

I just did 30K Rear LSD Diff and went with Mobil 1 SYN 75W90 and did not add any modifiers since i called Mobil and they said it did not need anymore? BIG BS on that my rear end was growling like a power sterring pump with no fluid in it! Sound was coming from rt front of truck it seemed but dealer drained and put dino valvoline 80W90 with modifiers in rear diff instead of draining out enough fluid to just add modifier to exisiting fluid, noise has gone away and it was no chattering in this noise it was a loud growling and glad it's gone!

[djosephm]

I use Lucas Heavy Duty Oil... I think it was either 75 or 80w 90

[RitcheyRch]

Mobil 1 SYN 75W90 here as well. Dont have LSD so no modifiers needed.

[HOGWILD]

yep i noticed the thickness of the rear diff fluid when i removed drain plug but had been lied to by Mobil Oil that it did not require extra modifiers and i did not put extra and dealership just changed it and noise went away? I mean it was growling BAD! why they did not just add modifiers i do not know but it was valvoline 80w90 & modifiers and they have been around longer than me so it will be good till 60 K and i will order some Torco F modifier before i go back synthetic and do the full 6% modifier with the Mobil 1 and see if it makes the growling then!

[Big_Al1]

Go with royal purple 75-90 no additive needed been running mine for 6k or so no growning or any strange sounds.

[djosephm]

Lucas!!!

[HOGWILD]

Like i mentioned i am partial to Mobil Oil and will just put the required addative next 30K interval and be happy!! did not mean to start a moaning product loyalty thread and i appologize it has went that direction! was not ment to be one!!

[djosephm]

Originally Posted by HOGWILD

yep i noticed the thickness of the rear diff fluid when i removed drain plug but had been lied to by Mobil Oil that it did not require extra modifiers and i did not put extra and dealership just changed it and noise went away? I mean it was growling BAD! why they did not just add modifiers i do not know but it was valvoline 80w90 & modifiers and they have been around longer than me so it will be good till 60 K and i will order some Torco F modifier before i go back synthetic and do the full 6% modifier with the Mobil 1 and see if it makes the growling then!

What the hell is a modifier?

Dude... you don't need additives to change differential oil. It is wise to change differential oil as the time to do so arrives... I forget the proper mileage, but I believe the norm is 60,000 miles to change your differential fluid. Of course this can change if you tow a lot of stuff. You simply drain all the old oil out of the differential and put new gear oil in.

[canddmeyer]

I've always added the modifier, even when I used synthetic. Never had any issues.

[Tundradrenalin]

the additive/modifier is for the LSD oil. HOGWILD is a man that follows his manual, some might say religiously. Manual says add the modifier and change every 30k. Oil manufacturer may say differently.

Just like Jiffy Lube says every 3k, Amsoil says every 15k, and Toyota says every 5k for crankcase oil changes. Jiffy Lube sells service, Amsoil sells product, and Toyota sells engines (with cars & trucks attached).

[HOGWILD]

Actually Mobil 1 says their 75W90 is ok for LSD Differentials and has modifiers in it and like i mentioned i called and asked prior to change and they said no problem it will not need any extra modifiers,but obviously their is not enough for A LSD Rear Differential? My rear diff growled till the modifiers were added.
Welcome to TORCO ADVANCED LUBRICANTS Website 2007 this should clear up what a modifier is? never hurts to do things the way the book says or a tad beyond if you can afford it! I guess being a Quality Assurance Inspector in the Air Force ruined me forever, NOT! My father who owned a full service ESSO/Gulf/EXXON for 38 years instilled a sence of pride in doing a job the correct way the first time and i wish i had of paid more attention to him!
As mentioned modifiers are for rear diffs with LSD! and yes most will have the sticker on back side of rear diff.
My owners service booklet says change every 30K what does your book say? I tow across NM, AZ,Colorado and Texas so it deserves new oil on occasion.

[12oreo]

I recently called Toyota CA and they told me it was ok to use 80w90 since 90w is impossible to find and gave me a case number. I used Valvoline Durablend 80w90 at 30k and have not noticed any chatter.