Recommended Z4M diff oil and interval

[imom]

Hi,
I spent quite some time searching before posting. So what's the consensus here... do I need OEM differential oil from BMW? Also do I need the one with friction modifiers? My M has 29K miles on it.

How often am I supposed to change the differential oil? I see some say 20K, some say 30K. I never track my car...just a daily driver.

So here's what I found from the search:

no FM booster the part number is 83221467993
SAF-XJ + FM Booster 83222282583--$135.00
Drain plug 33117525064--$3.27
Fill plug washer 07119932112--$0.07
14mm hex short--$9.74

I read some use royal purple max gear and some use redline 75-140w. With it being limited slip...do we need the Friction modifiers?

Also I take it that our Ms take a 14mm hex and not the 12mm?

Since I'm getting brake flush done...I like to change out the differential oil if needed. I just not certain what the correct intervals are because some track while others like me do not. Thanks for reading.


*** added note for myself - 1.1 liters required so 2 Quarts needed to make up for the .1 liters.

Brakes require 1 liter, so 2 bottles of 500ml. ***

[thekurgan]

I do mine every 30, and for the fluid, unless you have had the SIB groaning issues, I'm not sure you want to use the FM booster part number. I stick with the OEM fluids myself and I was told, and not sure if it's true, but if you use the FM booster fluid, it's what you'll need to keep using for the life of the diff. Someone please confirm this as my indie almost put in the FM part number before I intercepted them. I don't track the car, and change the brake/clutch fluid yearly or sometimes every 6 months, I live in an area that varies the temp quite a bit.

[tekmoe]

Running Redline 75w140. No grinding issues ever...

[imom]

Tekmoe, I saw your post...that's why I posted this... just wondering how many went with aftermarket vs. OEM diff oil. Engine oil, I heard to stick to stock, but the tranny I know to go with RP...so what's the deal on diff oil. Is there a consensus of folks switching or are you in the minority when it comes to diff oil. I'm not familiar with changing the diff oil so often, but if that's what is recommended...I like to make sure all runs well.

Very good to hear you had zero issues with redline... it's probably less expensive too... so how many others are there that stuck with OEM vs aftermarket like Royal purple or redline etc... and how often do you really need to.

[SmartBastard]

I do it with all the other oils at once, BMW recommends changing oil every 20k or 25k km if I remember well, I do one in between but that's cause I'm pushing the car hard time to time.

So far only stock oil.

[mjposner]

I use redline in my transmission and diff and would change every 25-30k or so.

[chickdr]

What is the time interval? I have an 06 with 14k miles. The 1200 mile service was done at 4k(2007) so the current oil has 10k and about 4yrs on it. Should it be changed earlier than 20k? I do brake fluid every 2yrs regardless of mileage.

[XMetal]

There should be no time interval in the diff and transmission because there are no other contaminants introduced into the system, unlike engine oil and brake fluid.

[thekurgan]

Originally Posted by XMetal

There should be no time interval in the diff and transmission because there are no other contaminants introduced into the system, unlike engine oil and brake fluid.

True, the oil just breaks down via mileage.

[BTM]

finally got around to my trans/diff fluid at 36xxx but plan on adhereing to a 30k interval for the next change. MTF-LT-2 and SAF-XJ

[Ron Stygar]

Originally Posted by chickdr

What is the time interval? I have an 06 with 14k miles. The 1200 mile service was done at 4k(2007) so the current oil has 10k and about 4yrs on it. Should it be changed earlier than 20k? I do brake fluid every 2yrs regardless of mileage.

Inspection II:

Replace transmission fluid

Replace differential fluid

In Z4 Bimmerfest FAQ

[beta]

Originally Posted by chickdr

What is the time interval? I have an 06 with 14k miles. The 1200 mile service was done at 4k(2007) so the current oil has 10k and about 4yrs on it. Should it be changed earlier than 20k? I do brake fluid every 2yrs regardless of mileage.

Your engine oil should be done every 2 years regardless of mileage as well. Since it's synthetic it degrades.

[XMetal]

Originally Posted by beta

Your engine oil should be done every 2 years regardless of mileage as well. Since it's synthetic it degrades.

The engine oil should be changed at least once per year, not because the degradation of the synthetic, but due to contaminants introduced by the engine's fuel blow by, condensation, etc.

[tekmoe]

Originally Posted by imom

Tekmoe, I saw your post...that's why I posted this... just wondering how many went with aftermarket vs. OEM diff oil. Engine oil, I heard to stick to stock, but the tranny I know to go with RP...so what's the deal on diff oil. Is there a consensus of folks switching or are you in the minority when it comes to diff oil. I'm not familiar with changing the diff oil so often, but if that's what is recommended...I like to make sure all runs well.

Very good to hear you had zero issues with redline... it's probably less expensive too... so how many others are there that stuck with OEM vs aftermarket like Royal purple or redline etc... and how often do you really need to.

They are all good. Royal Purple, Redline, Amsoil, Mobil1, Castrol. It doesn't really matter which one you go with, as long as its (for the most part) a full synthetic. My favorite is Redline simply because I've been using it for close to 10 years now and I've never had any engine problems on any of the vehicles I have had.

I trust the Castrol TWS in the engine. I saw someone post a Blackstone Lab report of it and they seemed to think it was still good and could have went to at least 10k miles before breaking down. At 7500 miles I was down by about half a quart. For this Texas heat, I'd say that's not bad at all. Engine seems to be running strong and is very smooth.

[chickdr]

Originally Posted by XMetal

The engine oil should be changed at least once per year, not because the degradation of the synthetic, but due to contaminants introduced by the engine's fuel blow by, condensation, etc.

I do the engine oil yearly and brake fluid every 2yrs. Is there a time maximum for the tranny/diff fluid?

[imom]

tekmoe, did you you the redline 75w140 with the friction modifier or the 75w140ns (without friction modifier)

[imom]

answered my own question... 75W140 is for limited slip application so FM is needed...that's what I read... correct me if I'm wrong.

[thekurgan]

Originally Posted by imom

answered my own question... 75W140 is for limited slip application so FM is needed...that's what I read... correct me if I'm wrong.

FM booster is only for vehicles exhibiting the groaning and shouldn't be needed otherwise. There are a bunch of threads concerning these two part numbers:

83 22 1 467 993

83 22 2 282 583

Look into both before you have the service.

[tekmoe]

From the Redline website regarding 75w140:

Originally Posted by Redline Website

Contains additional friction modifiers for suitablity with clutch-type limited slip differentials - for most LSDs, no additional friction modifiers are required.

I did not add any FM booster to mine. I just drained the stock crap out and poured in the Redline. Have never had a single grinding issue with either the stock fluid or Redline fluid.

[Ron Stygar]

Originally Posted by chickdr

Is there a time maximum for the tranny/diff fluid?

See #11.

[chickdr]

Originally Posted by Ron Stygar

See #11.

Thanks Ron, but this does not answer my question. I still have 8-10k(per my in car reminder) left until inspection I and my car is 5 yrs old. It could easily be 10yrs old whenl I hit inspection II. As other fluids have time as well as mileage limits I figured the diff/tranny oils may as well. Maybe not?

[Ron Stygar]

Originally Posted by chickdr

Thanks Ron, but this does not answer my question. I still have 8-10k(per my in car reminder) left until inspection I and my car is 5 yrs old. It could easily be 10yrs old whenl I hit inspection II. As other fluids have time as well as mileage limits I figured the diff/tranny oils may as well. Maybe not?

Someone mentioned in #8.

I change mine every 15K along with other things.

I'm at 18,513 on my 2006 M Coupe.