This is an overlay part for a broken parking brake cable retainer. BMW part number 34406854898 BMW Parking Brake Cable Retaining Clip. This is a common failure on many BMWs from 2010 to 2019. The noise is a scratching scraping noise during acceleration caused by the metal parking brake lines making contact with the driveshaft.

I was disappointed with the high cost of good quality parts and the poor fitment quality of the $16 amazon/ebay/aliexpress parts.

V1 is designed to fit with a new M8 nut and new washer up to 25mm in diameter. A thin washer is preferred. V2 is designed to reuse the original m8 nut with captive washer. The washer on my 2018 440i GC was 31.9mm which leaves the walls thinner than I would like. I did not validate this version. If you have an MMU/AMS and support filament, use the unsupported version. Turn off supports for the built in support version. The break and quality of the underside is show in the main pictures. The supports break away gently with pliers at the edge.

Printed on a Bambu P1P with 0.2 height and 3 walls. I suggest using PC or PA given the proximity to the exhaust.

I suggest preparing two in case you overtighten and crack the first print.

To add this replacement/fix... T60 to remove the (2) bolts from the subframe brace. T50 to remove the (6) bolts from the subframe brace. Pull the brace out 13mm socket to remove the two exhaust hanger brackets. Be sure to support the exhaust in some way. 10mm socket to remove the 6 nuts from the heatshield. Slide the heatshield aside or remove it if possible. 13mm wrench to remove the original brake cable retainer nut. Add the print over the broken OEM part. You may need to pull the cables apart a bit and push firmly up for threads to catch. Reverse order replace all the nuts and bolts. Take a picture and post it here if it helps you.