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!

 

[flyboy320]

Does anyone know the size or part number for the crush washer on the drain plug?

 

[Ollie]

Go to harbor freight and get the copper washer set on the cheap. In a pinch any copper washer will do. Even if you have to reuse an old one. Heat it up to red hot and quench it. It will return to a soften state and reseal just fine.

 

[Slithica]

I just got a large 300ml syringe and a rubber hose that filled the trans hole. I pumped in roughly 50ml more than what it called for to account for the 6" of hose and slight spillage.

I've done this 4 times. Works perfectly, super easy to change trans fluid.

 

[unL33T]

Does anyone know the size or part number for the crush washer on the drain plug?

Would it not be M16 if the drain bolt is M16? Which would also be the same size as the REX motor oil plug.

 

[BLINGMW]

I'm happy to be told this is dumb or won't work for some reason, but what if after draining, you jacked the right side of the car.... waaaay up. If it were 3ft off the ground with the car at a ~30deg angle, could you just pour in the 500ml with a funnel & short tubing?