Hi, changed my engine oil and filter today. the 10mm screws securing the undertray are half broken. The heads have sheared off, looks like rust then forced to open. I sheared 1 off too. So half of the threaded bit were inside only heads broken off. Some looks broken awhile ago, maybe by previous owner. Any suggestion to repair these? How do I get the remaining bits out?

 

I don't know of another way other than drilling them out.

 

try spraying with pb blaster and using reverse drill bits or a screw extractor.

 

Thanks guys. Fix some self tapping screws after drilling ?

 

if you used a small enough bit, you could retap with an M8 tap, if not, yes some self tapping screws would work.