[heticor]

I have been reading a lot about the recommended Oil form the front and rear differential.

According to Real Oem there is one for the front and one for the rear.

the front diff oil part number is 83222413511, Hypoid axle oil G2, SAE 75W-85 GL 5.
The rear diff oil part number is 83222295532 Hypoid axle oil G1, SAE 75W-85 GL4.

Many people uses the same oil from the front and rear, however they are different products. here a section of article that I found.

"When you are choosing a transmission or gear oil you might be wondering what GL-4 and GL-5 mean and what the differences are between these two classifications. Choosing the right classification is extremely important since they both have different properties and wrongful use could lead to serious damage to your vehicle.

There are four different classifications for transmission/gear oil. These different classifications define a certain level of performance in driven axles and manual gearboxes. They are mainly important for the transport sector in North America, Africa and Asia. The active classifications are:

GL-1
GL-4
GL-5
MT-1
The higher the Extreme Pressure (EP), the higher the GL category is. It is important to know that the SAE Motor Oil Viscosity Chart (J300) is different from the SAE Gear Oil Chart (J306). The viscosity has no relation with the API Gear Oil Classification and should be chosen based on the recommendations from the manufacturer based on the temperatures where you will drive.

The main difference between GL-4 and GL-5 gear oils is the amount of EP additives. Sulphur/Phosphorus containing products are used as EP-additive. This additive has the purpose to prevent the occurrence of micro-welds on the gear flanks at the local high temperatures which prevail in EP circumstances (temperatures well in excess of 800℃!) GL-5 has roughly twice the amount of EP additives compared to GL-4, which is why it is often used in high-pressure circumstances such as in a front axle and rear axle differential.

Sulphur/Phosphorus additives however have an unfavourable property: they can react aggressively towards bronze and copper. This can be disastrous for the synchromesh rings of a gearbox. Therefore it is not recommended to use GL-5 in a gearbox unless the manufacturer allows this.

To conclude:

GL-4 is suitable for hypoid gear service when they are under severe service but are without shock loading.
GL-5 is suitable for hypoid gear service under severe service and shock loads and not for use in a gearbox."

I am looking for the most economical but good quality oil for the differentials, what brand do you guys recommend?

[Bdavi011]

I used liqui moly differential oil om both my front and rear differential. I've replaced the fluid twice at this point. No issues. It's a GL5 rated.

I ordered from FCP Euro. They also have the genuine bmw differential fluid but it's about 3-4 times more expensive.

[Wgosma]

Just received this info based on my cars VIN - (2012 X3 N52 )….think I can do better on pricing with Redline, etc.?

[Wgosma]

Originally Posted by Bdavi011

I used liqui moly differential oil om both my front and rear differential. I've replaced the fluid twice at this point. No issues. It's a GL5 rated.

I ordered from FCP Euro. They also have the genuine bmw differential fluid but it's about 3-4 times more expensive.

I'm curious, did FCP advise that fluid you purchased was suitable equivalent for OEM fluid or ???

[Bdavi011]

Originally Posted by Wgosma

I'm curious, did FCP advise that fluid you purchased was suitable equivalent for OEM fluid or ???

It was not directly advised. More like I put my car info and it states that the fluid is compatible with my car. I honestly trust 90% of the brands/products FCP Euro has on stock. I have never had a bad experience with any Liqui Moly products so I continue to use them.

[Wgosma]

Originally Posted by Bdavi011

It was not directly advised. More like I put my car info and it states that the fluid is compatible with my car. I honestly trust 90% of the brands/products FCP Euro has on stock. I have never had a bad experience with any Liqui Moly products so I continue to use them.

I've definitely heard of Liquid Moly, in my prior BImmers I mostly used Redline gear oils, it's supposed to be good stuff too.
Thanks/Bill

[heticor]

I found this products:


for the GL 5

https://www.walmart.ca/en/ip/Red-Lin...RD3B3NUJ4OQA11

and this for GL 4

https://www.walmart.ca/en/ip/Red-Lin...RD2PWRN318YUK8


Redline has both oils spec, I do not hear too much about this brand, is it a reputable brand?

[spudslatte]

I purchased my diff oil from FCP Euro b/c the price seemed competitive and I could just enter my vehicle info and it gave me the proper Liquid Moly oils -

[Wgosma]

Originally Posted by heticor

I found this products:


for the GL 5

https://www.walmart.ca/en/ip/Red-Lin...RD3B3NUJ4OQA11

and this for GL 4

https://www.walmart.ca/en/ip/Red-Lin...RD2PWRN318YUK8


Redline has both oils spec, I do not hear too much about this brand, is it a reputable brand?

The company has been around for quite some time; their Lubricants are popular with the racing crowd and auto enthusiasts.

[heticor]

Originally Posted by Wgosma

The company has been around for quite some time; their Lubricants are popular with the racing crowd and auto enthusiasts.

Tank you for your feedback

[evilchargerfan]

I've seen alot of users go with Redline or LiquiMoly and are getting by just fine.




NOTE:
For my DD (an i3), I chose to stick with the OEM recommended Hypoid G1. It's an EV and I am not sure how the other brands will do. So I paid more for a little peace of mind.