If you hit a rock or a pot hole with your Volkswagen, one of the most vulnerable parts of the car may have been damaged: the oil pan. Located below the car, the oil pan collects oil that has already lubricated the car's engine. Replacing a cracked oil pan requires you to work under the belly of the car.
Engage the VW's emergency brake. (Even though the car isn't on, the emergency brake is a safety precaution, to help avoid the risk of the car sliding off the jack stands.)
Jack the car up by placing the car jack 6 to 8 inches behind the passenger side tire. If you look at this point you'll see an indicator that says where to place the jack. Be sure not to place it anywhere else or you can damage the frame of the car.
Place the jack stand below the car about a foot away from the tire on the frame. (This is to ensure the VW lifts up.) Lower the car on the jack stand by unwinding the car jack.
Jack the car up on the driver's side by placing the jack 6 to 8 inches behind the driver's side tire. Again, look for the indicator that shows exactly where to place the car jack. Once the car is lifted, place your other jack stand under the car just as you did on the passenger side.
Bring your new oil pan with you underneath the car. The oil pan looks like a metal box hanging down from the belly of the car directly below the engine.
Drain whatever dirty oil is left in the cracked oil pan by using your wrench to loosen the oil plug. Be sure to place the oil pan below the plug so that it will catch the dirty oil.
Use your ratchet set to remove the bolts holding the oil pan in place. Depending on the VW model, you may have to move the A/C compressor out of the way in order to reach some of the bolts on the oil pan. If so, loosen the serpentine belt, which twists around the A/C compressor's pulley, by locating the tensioner pulley. Press the bolt on the tensioner forward with your ratchet to disengage the tensioner, loosening the serpentine belt. Unwind the belt from the A/C compressor only. If you unwind it any more you may forget how it was routed around the other pulleys. If this happens, there is a diagram under the bonnet illustrating how the serpentine belt is routed. Once the A/C compressor is loose from the serpentine belt, pull it away from the oil pan to reveal the remaining bolts holding the oil pan to the car.
Besides removing the serpentine belt depending on your model, you may also have to turn your crank shaft. Have an assistant ratchet the large bolt sticking out horizontally from the crank shaft to allow you to reach any remaining bolts.
Pry the oil pan off with a large wedge if it doesn't come off easily after all the bolts have been taken off.
Clean and dry the mount with a scrub brush or paper towel where the new oil pan is to be placed.
Squirt a thin line of sealant on the surface of the new pan that will press against the car. Quickly bring the new oil pan to the mount and press it flat. Screw in a couple bolts to hold the new pan in place.
Tighten all the bolts with the ratchet set. If you had to have an assistant turn the crank shaft to turn some more bolts, do that again now to put in the remaining bolts.
The same is true for the A/C compressor: press the compressor back against the oil pan, insert the bolt that had held it in place, and use the ratchet to move the belt tensioner free so that you can wind the serpentine belt around the A/C compressor pulley.
Use the car jacks to remove each car stand one at a time.