Transmission oil change on a Rex from 2016 onwards

[Pipino]

You can use any clean container/PET bottle at height, connect the hose to it and fill it with the oil. This way you can keep the oil container to store the old oil.

 

[Chrism88]

Originally the set up included a 200ml syringe with a ~5 lb weight on it. But the seal in the syringe was not great and some oil bypassed it. It also did not go in much faster than under gravity (~4 ft).
I did get in all the oil in a very clean way.
Best set up that I can imagine now is: increase hole to 0.9mm or 1.0mm and connect the (1/4x1/8") hose directly to the cap of the oil container which is placed upside down on a high level, say 4-5 ft above gear box. make a pinhole in the bottom of the container to allow air in.

Is that 1/4” OD by 1/8” ID tubing you used? Also you mentioned loctite, do you think that’s necessary? Ordering BOM now.

 

[Timjohn]

Originally the set up included a 200ml syringe with a ~5 lb weight on it. But the seal in the syringe was not great and some oil bypassed it. It also did not go in much faster than under gravity (~4 ft).
I did get in all the oil in a very clean way.
Best set up that I can imagine now is: increase hole to 0.9mm or 1.0mm and connect the (1/4x1/8") hose directly to the cap of the oil container which is placed upside down on a high level, say 4-5 ft above gear box. make a pinhole in the bottom of the container to allow air in.

If you are going to make a batch of modified drain/filler plugs put me on that list.

 

[Chrism88]

I swapped the oil using Pipinos plug. A few things:

1. After 35k miles the oil looked almost new. Don’t really think this is worth it unless you just want to play around for fun. I think the oil is probably fine for 100k plus miles. In any case glad I did it anyway to clear the particles off the plug.

2. I overtorqued the hose barb and broke it so I had to improvise and set up something like it. I drilled into the top of the BMW oil bottle and the cap became a tool I’ll reuse in the future if I ever do this again.

3. It takes 3 hours or so for the oil to enter by gravity. The last bit I just closed the hole I made in the bottle (with a knife) and squeezed it which forced the rest of the gear oil up and in. Worked well.

4. I super glued the magnet to the plug. Maybe it wasn’t necessary, but I felt better doing that than not.

Thanks to Pipino!