[BE55]

Is it doable without removing pull rods?

[Jetnoiz]

Interestingly, I was under the rear differential today wondering about this too. I connected the following tools to access the plug:
Extension rod connected to half inch ratchet
Universal joint
14mm allen/hex socket
I stopped because I want to make sure there were no separate drain and fill plugs, correct? Additionally, I want to purchase new plugs with fresh seals before starting the procedure.

I look forward to additional replies.

[Vortex8]

There is only a fill plug, and it should be refreshed when changing the fluid so good thinking there.
You are lucky that you can access it without removing the rods. I have a vibration damper in the way and in order to get that one out I need to pull the rods, because I can't reach the damper screws otherwise...

[chr15gb]

How are you guys getting the oil out?

This is a job on my list of things to do.
I have an oil extractor I used to use for oil changes (no use to me now with no dipstick). I'm thinking of getting a small copper pipe I can bend to make a horseshoe shape to get into the bottom on the Diff. Then use the oil d extractor to suck the old oil out.

[Mkesler75]

Originally Posted by chr15gb

How are you guys getting the oil out?

This is a job on my list of things to do.
I have an oil extractor I used to use for oil changes (no use to me now with no dipstick). I'm thinking of getting a small copper pipe I can bend to make a horseshoe shape to get into the bottom on the Diff. Then use the oil d extractor to suck the old oil out.

That’s exactly what you do. I did both from and rear of my 2015 GT xdrive. Had no issues w access.

[SupremeF34]

I don’t think it’s possible to do without removing the bracing, unless you don’t have the harmonic dampener like Jetnoiz because that is pretty much blocking the drain plug.

I also removed my underbody bracing when I did mine and it was pretty easy. I did this service and made this video in fall of ‘22 but just getting around to posting it. It shows the entire process including removing the bracing Hope this helps.

[chr15gb]

Thanks for the video.
There are so many design layouts under these cars it's crazy
I couldn't find a single video the same as my 2014 335i.

I managed to do mine without removing anything in the way, just simple tools.
Not.much room available to break the bolt free but once broken free is easy to remove with fingers.

I used a pella 6000 oil extractor.
I taped the flexible end to a wire coat hanger to make the hook to reach the bottom.
Worked fine.
I did use a syringe with a longer tube you get with the new oil to fill but otherwise all straightforward.

[henitsl]

I did the rear diff fluid change on my wife's 2015 F34. I removed those bar rods and put them back without a problem. Wasn't a big deal. Just do it carefully. And I'm not a professional mechanic. Just had regular tools. Job is definitely doable.

[Jetnoiz]

I subscribed to SupremeF34/SupremeGT's YouTube channel a few weeks ago, and his recently posted video on the rear differential reminded me to check back on this forum. It's a useful video because it would give me courage to remove the pull rods. I haven't seen any other video that shows pull rod removal.

My damper, however, is located on the left side of the differential, above the rear left lower control arm, so the rear differential drain/fill plug was accessible without removing the pull rods on my GT.

To extract the fluid, I purchased 1 foot of 3/8 inch outer diameter flexible copper pipe from my local True Value hardware store for $3.17. 1 foot is slightly too long, but it worked. I inserted 4 plastic zip ties into the pipe to prevent the walls of the tube from collapsing before bending it to a U-shape.
The 3/8” outer diameter pipe fits snugly within the Red hose of the $7.49 Multi-Use Transfer Pump from Harbor Freight. Have someone hold the pump hoses in the bottle, otherwise clamp a heavy C-clamp to the bottle to prevent the stubborn hoses from tipping the bottle over while pumping. The copper pipe and transfer pump are cheaper alternatives to the adapter and fluid extractor from FCPEuro. I extracted 24 fluid ounces, therefore one quart of $23.59 Red Line 75W85 GL-5 Gear Oil 50104 (since the genuine BMW fluid is currently not available on FCPEuro) and one $6.29 STC-SP00176 BMW Differential Drain/Fill Plug sufficed.

[SupremeF34]

Nice!! Interesting the BMW 75w-85 wasn't available when you looked. Seems to be in stock now. Also didn't know the dampers were in different places on different cars. Seriously glad I could help. Was going to post the front diff video first but I realized I lost the last third of footage so I am going to do it again.

[alp06]

Its a easy job for begginers. Fill the new oil until it flews out from the hole and then close it again

[fliyer]

The easiest way is to shorten an Allen key to a length of 50 mm and then use a 14 mm ring spanner to turn it. Then you don't have to remove anything.

With an extension and joint, most people don't have the strength to loosen the screw.

[fliyer]

Hello,

I just wanted to show you a trick on how to change the differential oil on almost every F2X and F3X (most likely all BMWs) in under 5 minutes and without having to dismantle any components.

You get a 14mm Allen key and shorten it to 50mm in length.

A small mark on the screw to show the position saves you the torque.

Now you can put the Allen key and the 14mm ring spanner through both struts at the back.

Insert the Allen key into the screw by hand, push the ring spanner as far as possible towards the screw and open the screw.

I used a pump from Amazon for this, cheap but does the job perfectly. You just have to work a little more carefully and slowly, but it works.

Do the same thing the other way around and the filling is done.

Be careful, DIFF oil stinks when new, just as it does when old, extremely bad and it's hard to get out when washing.