Differential Fluid Change and Vehicle Position

[rantarM3]

Some of you may have noticed that the E90 M3 has a rake such that the side jack pads behind the front wheel sit about 1" lower than the rear ones. So if you put the car on a lift or on jack stands, the bottom of the car will be level with the floor whereas if you have it on ramps or on the ground, the bottom of the car will not be level.

So the question is whether this matters when changing the diff fluid. I was planning on doing it while the car is on a set of ramps (all four corners raised the same amount) but that means the car would be slightly tilted towards the front. I've changed my engine oil this way and had no problems.

Hope someone has some insight as I could not find anything on TIS about this.

[gatorfast]

When I did mine with a friend recently we just jacked up the passenger side rear, removed fill/drain bolts, lowered car bak down to allow it to drain, then filled it back up. However, I also had the exhaust off at the time which gave me a little more room to work.

I don't think you will have any problems doing it as you describe. But if you want to take a shortcut you can get away with raising the rear only.

[rantarM3]

I was primarily concerned with whether the car needs to be "level" or whether it can be done with the wheels level. These two things are not the same and if the car is raking towards the front, the diff fluid may accumulate in front of the drain plug. Maybe the angle is so little that it is of no consequence, which is what I think, but just wanted confirmation.

[Grail05]

just change them... if its level .. let it drip and put the new fluid in.. thats how the dealer do it. why make it complicated.

dealer puts it in lift remove fill bolt, remove drain bolt let it drain and fill it in with new fluid... simple

[W///]

You'll be fine. 1" isn't going to make a huge difference.