Note: this tutorial is geared for the V6, but should be similar for the I4.
Changing your oil is one of the more vital maintenance tasks for your car, and can be easily done by yourself. Oil changes should be done every 3000 miles.
NOTE: used motor oil is real nasty, hazardous stuff - make sure to wear gloves and old clothing as you will get oil on yourself.
Tools you will need:
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Going clockwise from the picture:
Ramp or jack/jackstands
Oil Collection Pan
Filter Wrench
Torque Wrench
5/8" Socket
Gloves
Oil Filter
Oil Plug Gasket (Size M14)
4.5 Quarts of Oil
Shop towels and/or Rags
Not Pictured:
Wheel Blocks
First thing to do is to warm up the car - the oil comes out quicker when it is warm.
Then put the car up on ramps or jack up the car. I like to use the ramps as it is quicker, but you don't get as much clearance with jackstands.
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Don't forget to set your parking brake and block off the rear wheels for safety as well.
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Next, pop the hood, and open up the oil filler cap.
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From underneath the car, place the oil collection pan under the car's oil plug. It's also a good idea to put some absorbant material under the collection pan as the oil can get everywhere.
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Remove the oil plug - remember, right tight, left loose. CAUTION, THE OIL WILL BE HOT! MAKE SURE TO BE WEARING GLOVES (I also use the rubber gloves that you use to wash dishes and that protects pretty well). If you have an open oil collection pan, be sure not to drop the oil plug into the pan (doh!). The oil should drain in about 3-5 minutes.
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While the oil is draining, clean off the oil plug and discard the old gasket. put the new gasket on the plug and set aside.
Inspect your new filter, and make sure the rubber seal is clean. Fill the new filter with oil. After the filter has been filled, take your (clean) finger and rub some of the oil along the rubber gasket. Set aside.
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Once the oil has finished draining, wipe the area around the plug opening clean and make sure it is free of debris. Carefully replace the oil plug with new gasket and tighten to 29 ft-lbs.
Move the oil collection pan to under the old oil filter. Use your filter wrench to LOOSEN the filter, then proceed to unscrew the old filter by hand - note that there is oil in the filter as well, so use caution as you remove the old filter. Drain the oil from the old oil filter and set aside.
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Clean the area where the oil filter was and make sure it is free of debris. Gently install the new oil filter, and tighten by hand only.
Almost done! Clean the area around the oil fill hole and feed yer baby some oil. Fill with 4.5 quarts of oil.
Take off the blocks and take your car down off the ramps or jackstands, and check the oil level with the dipstick - oil should be at the top notch.
Start the car and let it run for a bit. Look under the car and inspect for leaks. I also put some paper under the oil plug and filter when the car is sitting overnight to see if there are any leaks.
All done! Clean up, and dispose of the oil and old filter properly - most auto shops will take the oil off your hands.
Disclaimer: This guide is to be "used at your own risk". I take no responsibilities for errors, incorrect information, and make no representations or guarantees expressed or implied for any damages, mishaps, and/or pain and suffering that this may or will cause you.