Details around the F10 M5 Diff fluid change

[steeve13m]

Originally Posted by Fast400

I let mine drain for 45minutes.... 0.95 liters came out. Tried to squeeze more in, wasn't happening.

My mechanic had used a vacuum pump to drain oil and to add the 2 quarts

[Fast400]

Originally Posted by steeve13m

My mechanic had used a vacuum pump to drain oil and to add the 2 quarts

Maybe it was two 500ml bottles?
The factory puts in 1.2 Liters (1.4 qts) into a totally dry diff.

[Psquared]

I recently visited a dealer for rear diff fluid. They provided BMW part# 83222357992 for an F10 M5. I was hesitant this was the correct fluid as all websites I've crosschecked had a different part number (83222282583), and the bottle says +FM or "friction modifiers", this bottle doesn't say either.

I just went back to the dealer to verify they sold me the right fluid and the guy said the F10 M5 has a service bulletin out for the rear diff clutch packs crapping out, which now calls for the part # ending in 992 (above). Does anyone have access to this service bulletin, or can confirm the correct BMW part number for rear diff fluid as I'm getting mixed messages.

[steeve13m]

Originally Posted by Psquared

I recently visited a dealer for rear diff fluid. They provided BMW part# 83222357992 for an F10 M5. I was hesitant this was the correct fluid as all websites I've crosschecked had a different part number (83222282583), and the bottle says +FM or "friction modifiers", this bottle doesn't say either.

I just went back to the dealer to verify they sold me the right fluid and the guy said the F10 M5 has a service bulletin out for the rear diff clutch packs crapping out, which now calls for the part # ending in 992 (above). Does anyone have access to this service bulletin, or can confirm the correct BMW part number for rear diff fluid as I'm getting mixed messages.

I use "Lucas Oil LUC10121 SAE 75W-140 Synthetic Transmission and Differential"

works great

[Psquared]

Great. Thanks for the info. I returned the 992 fluid today and am going to go with either the Castrol Syntrax or Red Line fluid. Both say they have the friction modifiers and have great reviews. Now the dealer has me paranoid about the lsd clutch packs though...

[finlandm5f10]

Redline FM oil. Best you can buy.

[dsmclark]

I recently had my car in for service at my local dealer (just oil and filter) and they called me up to say the diff oil was low and so they were going to do a diff oil change. Only cost £50 and they discounted the oil change so it was all included in the original price I was quoted

[Psquared]

Did the rear diff drain and fill today using LiquiMoly fluid. Let it drain for 20 minutes after driving it for 30 to warm up the fluid. Exactly 1 qt came out, and that’s all it would take going back in. On another note, the LiquiMoly bottles have a pull out tube built into the bottle. This was super convenient, although you’ll still have to add a short section of hose to reach the fill hole. But I was able to use the tube and hose combo and simply squeeze the elevated bottle to get the entire quart back into the rear diff. I bought a second quart to have on hand, but didn’t need it. I also went with an ECS magnetic drain plug.

Another simple suggestion is to remove the rear metal undertray. Not totally necessary, but it made accessing the fill hole much easier, and it’s only 6 bolts. The edges of it are sharp as h*ll, so you’ll be doing your hands a favor too.

[kjdeion21]

Originally Posted by steeve13m

The OEM diff oil viscosity is rated at 75w140 so I will use the Lucas diff oil instead as it worked great on my last M5

Dealer said 3.17 quarts are needed for a flush change

https://www.amazon.com/gp/product/B0...A2BJUXTHZ4WM45

Wait what… you used Lucas oil!? You liked that!? I do not put anything an any of my cars other than mobile one fully synthetic but I went with the Castrol Transmax limited slip 75w-140 it's the best stuff for these cars hands down… there is a mobile one I think but I didn't find one and I was quick to wanting to change this… by the way you said over 3 quarts… is that because a full flush as it says only about 1.1-1.3 quarts… by the way no offense I just hate any American brand like Lucas oil STP all of those companies suck in my opinion I got an octane booster and I was using VP racing fuel and I even changed to the Lucas oil product and it sucks and STP is trash but anyways to each his own if you had a good experience then congratulations to you…