How to Read an Oil Dipstick
Knowing how to read an oil dipstick is something that many vehicle owners simply take for granted, assuming that everyone knows how. But people aren't born with the instinct of knowing how to maintain a car. These things must be learned to become second nature.
It is as important to know why to check the dipstick as it is to know how. Until a person becomes familiar with their vehicle's specific personality, it is a good idea to check the oil level as often as every fill up. This is part of proper vehicle maintenance. Some vehicles will have higher consumption of oil than others. Some vehicles will not have any measurable loss of oil between regular intervals of oil change, while others, particularly older models, will either leak or burn oil and need to be monitored more closely. Until you know about your vehicle's consumption level, it is important to check levels to make sure your oil does not become dangerously low.
In extreme cases, a motor will overheat and seize up when the oil level gets too low, resulting in a costly overhaul. Simple monitoring your oil consumption can prevent thousands of dollars in vehicle repair.
Vehicles with automatic transmission will have a dipstick for transmission fluid also in addition to an oil dipstick. The dipstick should be marked as to whether it is transmission or oil. To be certain (in the rare case there are no markings), the transmission fluid will be reddish colored, and motor oil should be amber colored. If it is dark brown or black, it is time for an oil change.
To check an oil dipstick, the motor should be OFF. The vehicle should be parked on a level surface. You should have a clean rag or a paper towel or something to wipe the stick.
Begin by pulling the oil dipstick out and wiping it clean. You will note there are some markings on the blade of the dipstick. A simple oil dipstick will have a full line (closest to the end), and a fill line. After wiping your stick clean, observe these markings. Now, take the stick and re-insert it into the engine. Be certain to push it all the way in until it seats in place. Now pull it out and look at the level where oil marks the stick. If it is at the full line, you are done. If it is at the fill line, you are down one quart. Anywhere in between the full and the fill line is in the safety range. It is time to add a quart if you have a reading at the fill line. If it is below the fill line (or not showing on the stick), you should add a quart and recheck the oil level after each quart you add.
You should NOT add a full quart if your oil level reading shows you are above the fill line. This will result in an overfill. It is not good to have more oil than full.
