I did not over tighten this oil filter. The problem is the top of the filter is flimsy and soft steel. When I first put the wrench on it, I was not able to apply any torque before the end cap began slipping. Regarding the surface of the end cap of the filter, you can push it in with your finger if you push hard enough. No way after 3000 miles of running, exposure to heat that it would stand up to the standard bmw endcap wrench. I have read on this board others who bought filters from beemer boneyard had same problem. And no, they are not mahle they are bosch. I bought their six pack deal (which I hope I can return) and they are bosch also. Walmart, I believe, sells bosch filters. Junk.