[Jamesjedi]

Hi,

How often to change gear oil? Car is 2015 M235 M Performance.

Thanks!

[Pray for Mojo]

I did mine at 60k km, I used the BMW fluid and a fluid transfer pump from Princess Auto.

[jb-slow]

I did mine at 60k with redline oil, holy shit did that oil smooth everything out. I highly recommend the redline stuff, it's butter smooth now. With the factory oil it would be hard to put the car in first sometimes, having to select another gear before trying first again. Since the switch it's never happened again, the shifter just floats into the next gear, it's fantastic.

[4Hockey4]

I used Redline also, and with Manual went with DCTF Dual Clutch Transmission Fluid Sku 31004.

After talking with Redline tech and BMW, the way to go. Made nice difference in shift. I did at 30K

Used RedLine for rear also. 75W85 GL-5 Gear Oil Sku 50104.

[Jamesjedi]

Excellent info. Redline? I am big on using OEM gear oil. I made a mistake in the past using a synthetic oil in an automatic transmission. It needed non synthetic.

A BMW tec said to use it?

[Jamesjedi]

I’ll check out the pump needed. I may have one.

[Jamesjedi]

I just ordered this pump from Amazon. Hopefully it will work?

[4Hockey4]

Originally Posted by Jamesjedi

Excellent info. Redline? I am big on using OEM gear oil. I made a mistake in the past using a synthetic oil in an automatic transmission. It needed non synthetic.

A BMW tec said to use it?

Tech said to use that "type" and they changed Redline oil and gear for me. Its 1/3 price of OEM at dealer, and they changed my oil for $35. There is a tech at my BME dealer that does lots of brake and fluid changes regularly for guys that track locally and he said many use RedLine or LiquidMoly.

Of course do your own due diligence etc. Redline tech will answer and chat through all of it if interested.

Cheers

[Jamesjedi]

Thanks. Very tempting. I wonder what the downside would be. I will do more research.

[Jamesjedi]

Contacted Red Line, here is the reply;

James,

Thank you for contacting Red Line Oil, in your M235i manual transmission the DCTF would be recommended and the 75W90 in the limited slip differential.

Regards,

Dave Granquist

[4Hockey4]

Originally Posted by Jamesjedi

Contacted Red Line, here is the reply;

James,

Thank you for contacting Red Line Oil, in your M235i manual transmission the DCTF would be recommended and the 75W90 in the limited slip differential.

Regards,

Dave Granquist

Yep I went 75W85 but pretty close. The DCTF made a nice difference on smoothness over stock.

[clamfroth]

I went with Red Line 75W80 MTL Gear Oil (SKU 50204) instead of the DCTF due to FCP saying it was acceptable to use in my '14 MT car.

Should I have gone with the DCTF or is what I purchased okay to use?

[4Hockey4]

Originally Posted by clamfroth

I went with Red Line 75W80 MTL Gear Oil (SKU 50204) instead of the DCTF due to FCP saying it was acceptable to use in my '14 MT car.

Should I have gone with the DCTF or is what I purchased okay to use?

I'll be honest, I called and pushed button for tech and he walked me through, than confirmed with my BMW tech. I went DCTF b/c they said for modern day trans it was smoother.

[Jamesjedi]

4hockey4, was your car lsd? Perhaps that is why they are different grades?

[4Hockey4]

Originally Posted by Jamesjedi

4hockey4, was your car lsd? Perhaps that is why they are different grades?

It is not, and possibly

[iv-128i]

Just did mine at 34000km , used ridline dctf, it is compatible with MTF-LT-5. At the same time changed my transmission bushings. Shifts are very smooth.

[Jamesjedi]

Shifter bushings? At 34000K. That seem low k for those bushings.

I will be trying the Red Line. Just need a warm day.

Thanks again for the reply’s.

[iv-128i]

Meant to say transmission mounts. Just wanted to upgrade to something more stiff.

[jb-slow]

Originally Posted by iv-128i

Meant to say transmission mounts. Just wanted to upgrade to something more stiff.

I did the m2 mounts while I was down there too, seems a little tighter without all the vibration like the aftermarket ones.

[Jamesjedi]

Is the LSD differential oil drain plug the same hole that is used to fill the differential? If so, I assume car must be level. Not easy on the driveway.