535xi Rear Diff--Poss. to Overfill?
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So I just changed my rear diff fluid for the first time since buying my '08 535xi last month. The car has 69k miles on it and I'm not sure it was ever changed. The fluid I suctioned out came out to about 2/3 litre. I pumped the new fluid in until it started overflowing, which amounted to about 1 1/3 litre--roughly double. Did I overfill?
BTW, the moaning/humming noise that was there before the refill when stepping on/off the gas at highway speeds is quieter, but not completely gone. Do I need a new diff?
BTW, the moaning/humming noise that was there before the refill when stepping on/off the gas at highway speeds is quieter, but not completely gone. Do I need a new diff?
Last edited by think3mm; 01-27-2017 at 05:16 AM.
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If the car was level when the differential was refilled, then the fluid level is correct when fluid reaches edge of hole.
N54 automatic. 1.0 ltrs (1.05 qts)
N54 manual 1.2 ltrs (1.27 qts)
N54 automatic. 1.0 ltrs (1.05 qts)
N54 manual 1.2 ltrs (1.27 qts)
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Thanks, jtb. It was mostly level, although I had the a**-end jacked up in my driveway so I could do the work; maybe 5" above resting level? That may explain why I was able to get 1.25 - 1.3L in there! Doubt it'll cause any issues, but next time I get to a level lift, I'll open the plug and let any excess drain.
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If it's an automatic, believe I would correct it. Overfilling can be just as bad as underfilling...
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Bentley doesn't differentiate between AWD and RWD on the differential, only between Manuel and Automatic That is where the fluid fills for the N54 came from.