GM Buick/Oldsmobile/Pontiac/Full-Size 1975-1990 Repair Guide

Engine

Print

OIL LEVEL CHECK



See Figures 1, 2 and 3

Every time you stop for fuel, check the engine oil as follows:

  1. Make sure the vehicle is parked on level ground.
  2.  
  3. When checking the oil level it is best for the engine to be at normal operating temperature, although checking the oil immediately after stopping will lead to a false reading. Wait a few minutes after turning off the engine to allow the oil to drain back into the crankcase.
  4.  
  5. Open the hood and locate the dipstick which will be on either the right or left side depending upon your particular engine. Pull the dipstick from its tube, wipe it clean and then reinsert it.
  6.  
  7. Pull the dipstick out again and, holding it horizontally, read the oil level. The oil should be between the FULL and ADD marks on the dipstick. If the oil is below the ADD mark, add oil of the proper viscosity through the capped opening in the top of the valve cover. See the Oil and Fuel Recommendations chart in this section for the proper viscosity and rating of oil to use.
  8.  
  9. Replace the dipstick and check the oil level again after adding any oil. Be careful not to overfill the crankcase. Approximately one quart of oil will raise the level from the ADD mark to the FULL mark. Excess oil will generally be consumed at a faster rate.
  10.  



Click image to see an enlarged view

Fig. Fig. 1: Checking the engine oil level with the dipstick.



Click image to see an enlarged view

Fig. Fig. 2: The oil level should show between the "ADD" and the "FULL" marks.



Click image to see an enlarged view

Fig. Fig. 3: Add oil through the capped opening in the valve cover.

OIL AND FILTER CHANGE



See Figures 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 and 15

The oil in the engine of your Buick, Olds or Pontiac should be changed every six months or 7,500 miles, whichever comes first (except turbo V6 and diesels). If you live in an extremely dusty or smoggy area, or drive for moderately short distances in cold weather (less than four miles with the temperature below freezing), change your vehicle's oil more frequently. The oil should be changed every 3,000 miles or four months under these conditions. A new filter should be installed with every oil change. The used oil should be placed into a suitable container and taken to a collection or reclamation point for recycling (many garages and gas stations have storage tanks for this purpose).

GM recommends that the filter be changed every other oil change, unless the vehicle is driven under those conditions requiring more frequent changes or those in which the time limit expires before the mileage limit. Our recommendation is that, regardless of the interval, the filter should be changed at every oil change. This offers excellent protection against a situation in which the filter becomes clogged, bypassing dirty oil directly to the engine's wearing parts. It also permits a more complete removal of dirty oil from the engine's filter and oil galleries, which hold a quart or more of contaminated fluid. Change the oil in turbocharged vehicles every 3,000 miles; change the oil in diesel vehicles every 5,000 miles. On diesels, if you are towing a trailer, if it is dusty, or you are driving trips of four miles or less in below freezing temperatures, change the oil every 2,500 miles or three months, whichever comes first.

The oil should always be changed while hot, so the dirt and particles will still be suspended in the oil when it drains out of the engine. To change the oil and filter:

  1. Run the engine until it reaches normal operating temperature. Once the engine is at normal operating temperature, turn the engine OFF.
  2.  
  3. Put the transmission in PARK , set the parking brake and jack up the front of the vehicle. Support the front end with jackstands.
  4.  
  5. Slide a drain pan of at least 6 quarts capacity under the engine oil pan.
  6.  
  7. Loosen the drain plug. Turn the plug out slowly by hand, keeping an inward pressure on the plug as you unscrew it so the hot oil will not escape until the plug is completely removed.
  8.  


CAUTION
When you are ready to release the plug, pull it away from the drain hole quickly, to avoid being burned by the hot oil.

  1. Allow the oil to drain completely and then install the drain plug. DO NOT OVERTIGHTEN the plug, or you will strip the threads in the drain hole and you'll have to buy a new pan or an over-sized replacement plug.
  2.  
  3. Using an oil filter strap wrench, remove the oil filter. Keep in mind that it's holding about a quart of dirty, hot oil.
  4.  
  5. As soon as you remove the oil filter, hold it upright until you can empty it into the drain pan. Dispose of the filter.
  6.  


CAUTION
The EPA warns that prolonged contact with used engine oil may cause a number of skin disorders, including cancer! You should take every effort to minimize your exposure to used engine oil. Protective gloves should be worn when changing the oil. Wash your hands and any other exposed skin areas as soon as possible after exposure to used engine oil. Soap and water, or waterless hand cleaner should be used.

  1. Using a clean rag, wipe off the filter mounting adaptor on the engine block. Be sure that the rag does not leave any lint which could clog an oil passage.
  2.  
  3. Wipe a coating of clean engine oil on the rubber gasket of the new filter. Spin it onto the engine by hand. DO NOT use the strap wrench. When the gasket starts to snug up against the adaptor surface, give it another 1 / 2 - 3 / 4 turn by hand (check the instructions provided by the filter manufacturer). Don't turn it any more, or you'll squash the gasket and the filter will leak.
  4.  
  5. Refill the engine with the correct amount of fresh oil through the valve cover cap, or breather tube (diesels). See the Capacities Chart located in this section.
  6.  
  7. Check the oil level on the dipstick. It is normal for the oil level to be slightly above the full mark right after an oil change because the filter and engine oil passages are dry. Start the engine and allow it to idle for a few minutes to fill these passages and the filter.
  8.  


CAUTION
Do not run the engine above idle speed until the oil pressure light (usually red) goes out, indicating the engine has built up oil pressure.

  1. Shut off the engine and allow the oil to drain back down for a few minutes before checking the dipstick again. Add more oil, if necessary. Check for oil leaks around the filter and drain plug.
  2.  



Click image to see an enlarged view

Fig. Fig. 4: Keep an inward pressure on the plug as you unscrew it so the oil won't escape until you pull the plug away.



Click image to see an enlarged view

Fig. Fig. 5: Use a strap wrench to remove the oil filter.



Click image to see an enlarged view

Fig. Fig. 6: Apply a light coat of oil to the rubber gasket on the oil filter before installing it.



Click image to see an enlarged view

Fig. Fig. 7: Install the new filter by hand. DO NOT use the strap wrench.



Click image to see an enlarged view

Fig. Fig. 8: To drain the oil, start by loosening the drain plug on the oil pan with a wrench



Click image to see an enlarged view

Fig. Fig. 9: Remove the plug the rest of the way by hand while keeping an inward pressure as you unscrew it. Quickly pull the plug away to keep the oil from running over your hand



Click image to see an enlarged view

Fig. Fig. 10: Allow all the oil to drain into a pan for several minutes and reinstall the drain plug when done



Click image to see an enlarged view

Fig. Fig. 11: Use a strap wrench to remove the filter only. Install the new filter by hand, be sure to coat the gasket with oil



Click image to see an enlarged view

Fig. Fig. 12: Remove the oil filler cap



Click image to see an enlarged view

Fig. Fig. 13: Place a funnel into the filler and add the correct amount of oil, be sure the drain plug has been reinstalled



Click image to see an enlarged view

Fig. Fig. 14: Locate the oil level dipstick and pull it out



Click image to see an enlarged view

Fig. Fig. 15: Wipe the dipstick and check the oil level, add if necessary

 
label.common.footer.alt.autozoneLogo