Ask a Mechanic | Grease VS. Thread Locker: Are You Safe? Ask a Mechanic | Grease VS. Thread Locker: Are You Safe? Daniel2015-12-16T16:17:23-08:00 Question: I see a lot of mechanics using grease on bolt threads and on Ask a Mechanic | Grease VS. Thread Locker: Are You Safe?Daniel2015-12-16T16:17:23-08:00