I have been slowly compiling the tools/fluids I need for a differential oil change on my 2012 BMW E92 M3 for the last few weeks. Trapped at home, what better time to do the work.

I opted for Castrol branded Syntrax 75w-140 fluid. The OEM fluid in the USA is Syntrax 74w-140 with a whole bunch of friction modifier in it. Extra friction modifier was added because there were people complaining about their differentials making a bunch of noise. To much friction modifier can also cut away at the performance of the differential.

Which one of you bought the performance benchmark from 2008-2013 and complained your amazing performing differential was too loud? I would like to have a talk with you.......

I also needed to get a 14mm HEX socket, just an oddball socket I never needed before.

Danny Korecki Danny Korecki

I backed my M3 up on Race Ramps to get it to be level on my incline driveway. It also provided easier access for me to get to the differential.

I recommend (and I think everyone does), that at least try to loosen the fill bolt first. The last thing you want to do is drain the bottom drain bolt and when it's time to fill, your top fill bolt is seized, you strip it, or some other problem arises.

Danny Korecki Danny Korecki

I popped the bolt and then waited for the oil to drain. While I waited, someone kept me company.

Danny Korecki Danny Korecki

After it drained, I put the replacement drain bolt on (my kit came with two new ones), then torqued it down to 60nm.

Danny Korecki Danny Korecki

There are many routes you can take to get the new oil in the differential. While the bottles do feature a squeeze option, I recommend you purchase a third party bottle pump online and pump the differential oil into your diff, it makes it so much easier in my opinion.

I wrapped the pumps hose over my exhaust and then it just easily pumped in. I needed a little more than 2 bottles until it began to leak out of the fill hole. That is when you know it is time to put the bolt on and torque it down to 60nm as well.

While simply backing out of most driveways will get the differential lubricated enough, I recommend slow for the first 1-2 miles than go to your normal scheduled M3 hooning.

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