Monday, July 15, 2024 Detailed Auto Topics
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Changing your own oil is not for everyone. Some folks simply do not enjoy physical work and this is not for them. For those of us that enjoy the feeling of accomplishment that comes from work, I have included many details professionals use, to help do a great job.

Why change your own oil?


When you change your own oil, you control the quality

Many people understand just how important the oil change is to the life of their vehicle. They want the job done right and the best way to accomplish this is for them to do it. Unfortunately, many oil change places and even new car dealerships use very low skilled personnel for oil changes.

Making this worse is the speed at which oil change shops try to work. Time truly is money, and rushing through the job saves time. This is big mistake, as rushing provides less than ideal results. Changing your own oil allows taking as much time as needed.


Places that change oil normally see dozens of different models in a day. When rushed, looking up the information needed to properly service vehicles is very difficult. Engines today require specific types and viscosity of oil. Using the wrong oil may harm the vehicle. In a rushed environment, with poorly trained staff, a vehicle may get the wrong oil.

Another serious problem is stripped drain plugs, from a failure to use a torque wrench or look up the torque specifications.


To increase profits, oil change shops purchase oil in bulk, rather than in quart bottles. Nothing is wrong with bulk oil, if we store and dispensed it properly. They may neglect this in some oil change shops. Bulk tanks can sweat if not kept in a climate controlled environment. Oil stored in the tanks picks up the moisture and the client receives moisture-laden oil. Storage tanks should be kept in a dehumidified and climate-controlled area and should have desiccant filters on the vents.


Oil filters come in many grades. Many brand-name producers sell cheap imported lines. Doing the job yourself allows control of the oil filter quality.


Teaching a new driver how to change oil is a great way to instill responsibility for the vehicle. This knowledge goes far beyond the financial gain and helps start a lifetime of responsible vehicle care.


Unscrupulous operators often use loss-leader oil changes to bait the client in for profitable wallet flushes. Changing the oil yourself prevents this. It also allows the opportunity to glance under the vehicle and spot real service needed.

Finding the right oil

Before considering an oil change we need to find the proper viscosity and quantity of oil needed. This information is available in the owner’s manual of the vehicle. They normally also list the proper viscosity of the oil on the fill cap of the engine.

Substituting oil viscosity is not wise, especially on a modern vehicle. The recommending oil viscosity is also good for the life of the vehicle. No matter engine mileage, stay with the recommended oil. High-mileage formulas are more about marketing than engine needs. For instance, an engine that calls for 5W20 can use this viscosity for the life of the engine. High mileage does NOT change viscosity recommendations.

Engine oil also needs to meet other specifications and many vehicles today require either synthetic or synthetic blend. Failure to use synthetic oil in an engine that requires it will drastically shorten the life of the engine. On 2011 and newer GM products, oil must meet the dexos specifications. Using oil not labeled as meeting dexos standards may void the engine warranty. Always read the oil requirement specifications carefully and if in doubt asks a professional for advice.

Once we find an oil that meets the proper specifications, we must select a manufacturer's brand. This is important as changing oil brands can cause problems. Most major brand oils are good, if they meet the specifications of your engine. Different brands often use different additive packages and these may not be compatible. For instance if you use Mobil do not switch to Valvoline or vice versa.

Torque and drain plugs 

Oil drain plugs should be tightened to specifications using a torque wrench

We will also need a torque specification for the oil drain plug. This is critically important and over-tightening the drain plug will result in expensive damage. This specification is sometimes in the owner’s manual. Shop service manuals also normally list oil drain-plug torque. If you register with, you will find oil drain-plug torque-charts, for Domestic and Asian vehicles by clicking here. AGCO will supply this information to you, if you email a request. We need a torque wrench to measure the torque  applied. Inexpensive torque wrenches are available for a few dollars at many part or tool stores.

Buying the oil filter

Along with the proper oil you will need an original equipment manufacturer (OEM) oil filter and a drain plug gasket, if used. On engines that use a seal that is integral with the drain plug, an extra drain-plug is a good investment. Having an extra drain plug in the tool box can prevent a great deal of anxiety, should we damage or misplace the plug.

The best place to purchase oil filters, crush washers and drain plugs is the new car dealership parts’ department. Also be aware that some dealerships also sell a second-line of oil filters. Always specify that you want the OEM filter.

Buying more than one filter at a time may be more convenient. If they stay in the original box and we store them in a climate controlled area, oil filters will keep for years.

Check the level before you drain

Clean, dirty and low oil readings on an engine dipstick

Checking the oil level and condition before draining can give you insight into the condition of the engine. For instance if the oil level is low, the engine may be burning or leaking oil. When checking oil be sure the vehicle is level and the engine has been off at least five minutes. This allows the oil to drain from the upper areas and run down to the pan, where we may measure it.

 various oil level readings on an engine dipstick 

Oil dipsticks are not precision instruments. A slight over or under filling is not critical if we have installed the correct amount of oil.

Draining the old oil

When oil sits, debris and sludge settle to the bottom of the pan. This is very thick and hard to drain when it is cold. Driving the vehicle until fully warmed before draining the oil is a good idea. Hot oi will carry more of the sludge with it as it drains.

 The drain plug should be the lowest point

Raising the vehicle on ramps or stands will greatly simplify the oil change. If the vehicle is not level, be sure the oil drain plug is the lowest point. For instance, if the drain plug is in the front of the oil pan, raise the rear of the vehicle and vice versa. This allows gravity to drain the contaminants better.

Let the oil drip as long as possible to remove the worst contaminants.

We should also let the oil drip for as long as possible. The worst contaminants are thick and take time to drain. We should allow oil to drain for at least 15 minutes. Several hours of drain time are even better, when time permits.

Installing the oil filter

Inspect the oil filter mounting area and wipe away any debris or oil. Occasionally the seal from the previous oil filter may detach and stick to the filter housing. If we do not spot this, the new filter could be placed over the old seal. This does not provide adequate support and the seal could blow out, causing the engine to lose oil pressure. Illuminating the area with a flash light will make inspection much easier.

Always lubricate the seal area with clean oil

Before replacing the filter, put a thin coat of clean oil on the seal area. Lubricating the seal will allow it to slide into place without binding. A dry seal may stick and pull away from the filter when tightened. The light coating of oil also allows easier removal at the next change.

Filling the filter may allow dirt to enter the engine

Many mechanics advocate filling the oil filter before installation. The thought is, this prevents the engine from running without oil.  In practice this is not a real concern.  Upon cranking, the filter will fill almost instantly with filtered oil.  Filling the filter will not help and may cause problems.

Bottled oil is very clean, but has not been filtered. Also any debris that enters the threaded opening of the filter will not pass through the filter element. An example may be the foil that seals the oil bottle or any debris on the bottle.  Oil poured into the filter is on the output side and is transported into the engine.  The oil pump pumps oil on the output side of the oil filter straight to the engine bearings.  Any debris that falls into the filter when filling will cause engine damage. 

The drain plug, seal and filling

Install the drain plug, with a new crush ring if used.  If the seal is part of the plug, inspect it and replace the plug if worn. The oil drain plug should easily thread in by hand until the seal contacts the pan. We then tighten the plug to specifications using a torque wrench. Lower the vehicle to level and add oil. Pour in one-half quart less oil than the engine holds. After a few minutes check the level and then add more if needed. Topping off several times is better than to over fill the engine.

Once the oil level shows full, we can start the engine and let it run for a few minutes. Shut it off and let it sit for a few minutes. Check the level a final time and adjust as needed. Also, be sure to check under the engine for possible oil leaks.

Remember to responsibly dispose of the old oil and filter. Many oil change shops will take these for disposal. Changing oil is easy and puts control of the quality in your hands.

Please also see our Detailed topics on Oil Change Intervals and Should You Use Synthetic or Regular Oil


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