When you change a timing kit do you have to put oil or grease in the new idler sprocket when installing it?
My car has an automatic transmission.
Hi and thanks for contacting YourMechanic. When it comes to removing and replacing any part to an engine that is always submersed in oil, it is good to put oil onto the chains, all sprockets and chain guides. I would recommend putting on Lucas oil brand or engine building grease onto the chain and sprockets for lubrication during startup. It will not hurt the chain or sprockets to start the vehicle up with them dry, however, it will damage the chain guides. So, yes I would recommend lubricating the new idler sprocket when installing it. If you need assistance in the sprocket installation, a YourMechanic certified technician can come to your location to help you with the timing kit installation.