Rear Differential fluid Mobil 1 or Royal Purple, and motor oil discussion.

[2010 Bumblebee]

Originally Posted by Dreamer2430

I'm heading out to my first road course, so I just did all of this today. I went with Mobil 1 for the motor oil and diff. fluid. Didn't specify the tranny fluid, but I always tell them to use the best stuff. It was a little pricey at the dealer, but my dealer has been great ($190 for the diff, $160 for the tranny and $50 for the oil.) Dealer actually tried to talk me out of it. They said that the tranny an diff didn't need to be changed until 30,000 miles.

Wow I get my oil done with mobil 1 (8 quarts) & filter at the dealer for $70.52. I thought that was a good price but yours is better, is that synthetic?

As far as the differential. I got a few quotes at $140, but I did my research. It is a quart of 75w-90 gear oil (about $10 at the parts store) and some LS additive ($10 at the dealer). 2.6oz of additive & the rest gear oil to fill to capacity of 1.1 quarts. You have a fill plug and a drain plug.

So , I haggled with my dealer and explained my case. They lowered the price to $28 for the gear oil + whatever the LS additive cost+ $44 labor.

All in all that's about $85 for the rear end much better than $140, and it is in their computer as done for warantee, a car fax, or something else like resale..

[Dreamer2430]

Originally Posted by 2010 Bumblebee

Wow I get my oil done with mobil 1 (8 quarts) & filter at the dealer for $70.52. I thought that was a good price but yours is better, is that synthetic?

Yes, that's Mobil 1 full synthetic. I have a "perferred owner" card for my dealer. They gave me a small discount on the other fluids as well. My total cost with labor ended up being $390 for all these fluids. Unfortunately about 1/3rd of that was labor.

[2010 Bumblebee]

Originally Posted by Reeko

From the Mobil Site.....

Mobil 1 Synthetic Gear Lube LS 75W-90 contains special friction modifiers designed for limited slip-type differentials. In most applications, the addition of special LS (limited slip) additives is not required. For axles requiring the highest level of limited-slip performance, OEM specific LS additives can be added to this fluid.

At.
http://www.mobiloil.com/USA-English/..._75W-90LS.aspx

I just got off the phone with mobil and they said if my car calls for the additive I still have to put it in. So what the heck is the LS on the bottle for???

1-800-ask-mobil

[motor1]

Originally Posted by 2010 Bumblebee

I just got off the phone with mobil and they said if my car calls for the additive I still have to put it in. So what the heck is the LS on the bottle for???

1-800-ask-mobil

I am definitely interested in any feedback on this because I keep reading no additive required from members

[franknbeans]

subscribing. . need to change my oil too.

[2010 Bumblebee]

Originally Posted by motor1

I am definitely interested in any feedback on this because I keep reading no additive required from members

Just to clarify I'm talking about the mobil 1 75w-90 LS rear end lube. I called the number on the bottle and asked them "is the additive in the gear oil?" I didn't get a straight answer, but he said "if you car calls for additive then you still need to put that additive in it."

So I'm thinking it is formulated for the additive, but kind of misleading because it says LS on the bottle. If you read the back of the bottle there is nothing about limited slip differentials there or the additive. At least I didn't see it there , that's why I called them.

1-800-ask-mobil

[franknbeans]

so no update then. . . i take it everyone that said their oil had the additive, were just guessing.

[5th_GEN_SS]

used rp... seems to be better

[2010 Bumblebee]

Originally Posted by franknbeans

so no update then. . . i take it everyone that said their oil had the additive, were just guessing.

I went to the dealer today and they put this "new" gear oils from GM in it that has the additive in it. I don't know what the mystery gear oil is.

[DarricSS]

I went around and around in circles as well when I wanted to get information on what type of gear lube I should use. I decided on going with 1 quart of Redline 75w90 because it does not require the friction modifier that is required for our "High Performance" rear-end. But I could not find any at the local auto parts stores and didn't want to take the time to order some.

So I went with 1qt of Mobile1 GL-5 75w90 and purchased the 4oz bottle of the friction modifier GM Part # 1052358.

Even in the link that Reeko provided it states to add the friction modifier to "highest level of limited-slip performance" I consider my car having a "High Performance" rear-end and added the 2.5oz of friction modifier and then topped off with the Mobile1 gear lube.

The Mobile1 gear lube I listed above is the same lube as the LS 75w90 they just changed the name so that people are less confused if it's meant for limited slip differentials.

My car drives smoother now and lays double black stripes just fine and there is not chatter around corners hard on the gas.


"From the Mobil Site.....

Mobil 1 Synthetic Gear Lube LS 75W-90 contains special friction modifiers designed for limited slip-type differentials. In most applications, the addition of special LS (limited slip) additives is not required. For axles requiring the highest level of limited-slip performance, OEM specific LS additives can be added to this fluid."
At.
http://www.mobiloil.com/USA-English/..._75W-90LS.aspx

[franknbeans]

how much was the bottle of GM Friction fluid?

[DarricSS]

Originally Posted by franknbeans

how much was the bottle of GM Friction fluid?

Was around 6 bucks from PepBoys. Comes in a 4oz tube so you will have some extra left over.

[RedJewel2SS]

i put the Mobil 1 75w-90 LS in mine. it was $10 per quart. the royal purple was $18 per quart. and the GM fluid from the stealership was $25 per quart and $15 for the tiny friction modifier bottle. all i bought was 2 quarts of Mobil 1 and that's it.

no offense to the guys running RP, but something about having purple dye in your oil makes me think it is a bad idea. just becuase they advertise like crazy on the TV, does not mean it is the best out there. Mobil 1 has been around a lot longer than RP and has been proven to whoop other oils asses in GM vehicles.

[Wacker]

Royal purple in the rear.