Fluid leak near AC compressor pulley

[JFP in PA]

Depends upon the condition of the AC compressor; these units have a front support bearing that can go bad, which tends to make the seal leak. If the bearing has gone bad, it can “rumble” which can be the cause of the shake you have when the system is active. You can test this by removing the engine cover behind the car’s seats and listening to the compressor when you switch it on and off.

What you will have to replace depends upon how bad the front compressor bearing is; if it is just wobbling and making noise, you either have it rebuilt or replaced. If the bearing has torn itself up, there will be metal bits all through the entire AC system which must be cleaned out or they will promptly kill the new compressor. This metal will be everywhere (the AC system is a high pressure, high flow system), so the drier and filter will need to be replaced, along with some other bits.

You also need to understand that working on the AC system is not a “backyard” DIY project; the system contains gas under pressure that needs to be removed and captured for recycling (it is an environmental hazard and many states require that AC repair facilities be licensed and keep tight records on gas recovery), which requires some pretty expensive tooling, so you may want to take it to a pro.