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How to Change Oil in Your C5
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Welcome to my oil change procedure page. After cobbling together lots of information from the web, I decided to take a shot at changing my C5's oil with 1,225 miles on the odometer. The oil looked very clean.
Below is the step-by-step process I used to complete the task, with pictures. I learned a few things along the way which I have documented here, and I hope this makes your first oil change a pleasure rather than a pain.
- 15mm box wrench
- Cap wrench to remove the old filter (a strap wrench might work but is very difficult to maneuver into position)
- (2) Rhino brand ramps
- (2) Bricks or other means of blocking the front wheels
- Floor jack
- Torque wrench with 15mm socket and filter wrench adapter
- 5 lb. plate barbell weight (or equivalent)
- (2) Lift pads (or equivalent)
- (2) Jack stands
- An oil drain pan that holds more than 6.5 quarts of fluid
- 6.5 quarts of Mobil 1 5W-30 synthetic motor oil (or equivalent)
- You must use oil that meets or exceeds General Motors standard GM4718M and which is 5W-30 in order to maintain your new factory warranty. It is important to note that not all synthetic oils will meet this standard. Make sure to look specifically for this standard when purchasing oil for an oil change. You may use oil that doesn't meet this standard. Only to top off your system in an emergency, but do not use oil that does not meet this standard for an oil change.
- You may also use 10W-30 that meets this specification if it is going to be above 0 degrees F (-18 degrees C).
- Do not add any additives to the oil.
- AC-Delco UPF44 Ultragard Oil filter (or equivalent)
Let's Get Started
When to Check Your Oil
Check your oil regularly - I use once every two weeks as a good time to check. Otherwise, if your LOW OIL LEVEL indicator is illuminated, pull over immediately and check.
When to Change Your Oil
This is a topic of heated debate. It seems that some go by the classic "Change your oil every 3,000 miles for best results" while others prefer to change the oil when the DIC tells them to. It is my engineering-minded belief that with today's technology in both mechanics and chemicals, changing the oil somewhere between the 25% and 0% oil life remaining indicator on the DIC is the best way to go. GM used a pretty advanced algorithm for the DIC to determine how fast the oil life reading changes from 100% to 0%, taking into account such things as engine revolutions and engine operating temperature. I think the DIC is relatively accurate and plan to change my own oil at the 20% to 25% oil life remaining mark. The system doesn't detect dust, so if you drive in dusty environments change the oil before the DIC indicates that its time to do so.
This is a personal choice and you should make the best choice for your particular car and driving habits. One thing to remember is to never let your oil go past 10,000 miles before changing it. I'd also recommend changing the filter and oil at the same time. Even if you choose to let the oil go for 10,000 miles between changes, try to change the filter at least twice as often. It's cheap insurance against engine damage.
- Make sure the oil is partially warm - do not change oil when cold. A good temperature is in the low 100 degree Farenheit range. If you change the oil when hot (above 125 degrees F) I suggest the use of Mechanix gloves to prevent burns.
- On level ground, carefully position the Rhino ramps and drive the front of the vehicle on to the ramps as shown.
- Set the parking brake and place the transmission in Park (A4) or 1st gear (M6).
- Place the bricks (or equivalent) directly behind the tires on the ramps as shown. This is an important step because if not done, the vehicle may roll backward when the rear is being jacked up (setting the emergency brake and placing the transmission in gear won't help when the rear end is off the ground).
- Find the proper rear jack point, which is the large crossmember behind the rear leafspring and in front of the rear anti-swaybar. It has two large braces as shown below.
- Place the 5 lb. plate weight (or equivalent) on top of your floorjack such that the weight is both centered on the jack plate and spans both aluminum ribs on the crossmember as shown, taking care to place the jack in the center of the crossmember as viewed from the rear. NOTE: It has been mentioned to me that a weight such as this might actually crack under this type of stress, so using a piece of wood or other solid, heavy, flat material might be a better choice.
- Carefully jack the rear of the vehicle.
- Place the jackstands underneath the rear crossmember as directed by the shop manual (Please note: if you have specific information from the shop manual, e-mail it to me so I can place it on this page for completeness).
- Carefully lower the rear of the vehicle onto the jackstands. Make sure that the rear is at least an inch or two above the front to ensure a proper drain.
- Place the drain pan below and to the front of the drain plug, which is located on the "bat wing" aluminum oil pan as shown in the next step's picture.
- With the vehicle suspended in the air, remove the oil filler cap and slightly lift up on the dipstick such that it is not seated fully. This relieves the pressure and many believe that it helps the oil flow much faster, helping contaminant removal as well.
- Remove the drain plug using your 15mm box wrench and allow the oil to drain from the pan until it becomes a slow trickle or stops (10 to 15 minutes should do it, but some folks let it drain overnight). Shown below is what your view of the oil draining will look like.
- Replace the drain plug (I chose to purchase an official GM magnetic drain plug for $2.50 from any GM dealer) and tighten to 18 lb-ft using the torque wrench or until you are satisfied that it is tight enough. Do not over tighten the drain plug; the repair for damage may cost you your next child!
- Move the drain pan directly below the oil filter.
- Slowly begin removing the oil filter. An filter wrench (open ended) may help, but I was able to use a strap wrench to do the trick. When oil starts flowing, allow it to drain until it becomes a trickle. Completely remove the filter and wipe the mating surface clean of debris and oil as shown. Please note that the shop manual recommends removing the filter while the oil is still draining from the oil pan, but most DIYers will have trouble with this due to the limitations of their drain pans (size).
- When oil has stopped flowing, replace the filter with a new one (UPF44 or equivalent). Make sure to lightly oil the gasket on the new filter before installation. You may also choose to pre-fill the filter with as much oil as you can; it's up to you. Tighten to 22 lb-ft with your torque wrench, which should be the equivalent of about 2 to 3 full turns after the gasket makes contact with the pan. Please note that many of us choose to hand tighten the filter to 1 full turn after contact, and have not seen any problems associated with this method as of yet.
- Lower the rear of the vehicle by reversing the steps above.
- Open the oil filler cap under the hood and put in 6 quarts of oil. We'll top it off in a minute. Do not start the car yet!
- Wait a minimum of three (3) minutes for the new oil to fill the oil pan before starting the engine.
- Replace the filler cap, and push the dipstick back into place, and start the car. Let it run for a few minutes.
- Check for leaks around the filter and drain plug. Correct any problems you see now, before the front end is off the ramps.
- Back the car off of the ramps, and then shut it off.
- After waiting at least five (5) minutes, check the oil level. It should be a bit low, but don't worry - we'll add more shortly. Waiting for the oil to settle will yield a much more accurate reading than checking immediately after shutting the car off. It is better not to risk overfilling the vehicle.
- Put in one half quart of oil, then start the car again. Let it run for a minute or two.
- Shut the car off.
- Check the oil level. It should be at the top of the "Full" range on the dipstick.
- Reset the "OIL LIFE" indicator on the DIC.
- Clean up; you're done!
How to Reset the "Oil Life" indicator
After an oil change, you need to reset the oil life indicator so that you know when the next change is due. Here is how to do that.
- Turn the ignition on, but make sure the engine is off.
- Press the "Trip" button on the DIC so that it displays "OIL LIFE" percentage.
- Press and hold the "Reset" button for two seconds. "OIL LIFE REMAIN 100%" should appear on the display.
This page was last updated on 05/28/01 by Redshift