Most engine hardware including head studs, VANOS bolts, and exhaust studs can only be used once. While most of the accessory bolts and miscellaneous hardware can be re-used it is often handy to have a spare bolt or bracket just in case one breaks. Any aluminum bolt, such as those found in the N52 engine MUST be replaced no matter the age or visual condition.
This Genuine BMW engine hardware and seal kit is put together to ensure your timing chain and VANOS system are bolted back down with complete reliability.