[bin01123]

Changed the transmission fluid & filter on my F10 535 at 90K and I’m currently at 92K miles. (Used OEM fluid & filter) I’ve been getting a smell of transmission fluid in the cabin ever since I changed it. I checked underneath the vehicle for any leaks and didn’t find anything nor do I get any leaks on my garage floor. I’ve also changed the filter and fluid at 50K without this issue so I’m kinda lost this time around as to why I’m getting the smell. I thought the smell may go away after a while but its still here after 2K miles. Does anyone have any ideas what may be causing this?

[bin01123]

Would this happen with an overfill?

[Sophisticated Redneck]

Originally Posted by bin01123

Would this happen with an overfill?

I would check the transmission heat exchanger and the hydraulic lines that run to it for leaks too as that may be the source. Overfill could cause it but one would think you would have to overfill to an extreme amount to make it vent fluid out the top vent on the transmission and surely it would have shifting problems too. How much oil did you put back in? Assuming it's the ZF8HP45, normal amount is 4 to 4.5 liters for a standard oil change.

[bin01123]

Originally Posted by Sophisticated Redneck

I would check the transmission heat exchanger and the hydraulic lines that run to it for leaks too as that may be the source. Overfill could cause it but one would think you would have to overfill to an extreme amount to make it vent fluid out the top vent on the transmission and surely it would have shifting problems too. How much oil did you put back in? Assuming it's the ZF8HP45, normal amount is 4 to 4.5 liters for a standard oil change.

Originally Posted by Sophisticated Redneck

I would check the transmission heat exchanger and the hydraulic lines that run to it for leaks too as that may be the source. Overfill could cause it but one would think you would have to overfill to an extreme amount to make it vent fluid out the top vent on the transmission and surely it would have shifting problems too. How much oil did you put back in? Assuming it's the ZF8HP45, normal amount is 4 to 4.5 liters for a standard oil change.

Oh no. I definitely overfilled. I had 1 quart and a half reaming of the 7 I got with the kit. I recently let some drain (1 quart came out) from the fill hole and the smell reduced a lot. Going to monitor it for now and see how that goes. I've got an extra unopened quart just in case it gets too low.

[bin01123]

So I drained 1 quart from the fill hole and I'm now 3100 miles post the transmission oil and filter change. The smell has reduced but is it supposed to last this long before fading away?