BMW Transmission Fault Code 4F81 (Ratio monitoring, clutch A)

Transmission Fault Code 4F81 (Ratio monitoring, clutch A) is becoming a frequent repair here in the shop. We know it’s a common problem with this transmission in gerneral so I thought I would share with everyone what the issue is and what the required repair will likely be.

2006 BMW 750i


What you may be experiencing is your transmission is not shifting properly, not engaging into gear or is in “failsafe mode”. Your dashboard and idrive will likely indicate that there is a transmission fault or failure present. I recently posted a video on YouTube that I took the last time I performed this repair. It’s not an outrageous repair so don’t be too scared of what the cost will be. Likely, you will spend between $550-$750 depending on whether you opt to refill with new fluid at roughly $30/liter. Keep in mind there could be a diagnostic charge as well, we do not unnecessarily put parts on cars without properly diagnosing the problem first.

Here is the video link.

And this is the BMW SI Bulletin

SI B 24 01 08 Automatic Transmission