What is a dipstick and where is it located?

The dipstick may very well be on its way to becoming a quaint, antiquated relic of the past. As manufacturers are developing newer cars with more sensors and computer moderated systems, the simple act of sliding out your dipstick to check the engine's oil level may be replaced by a much more convenient system that simply alerts you when your engine or transmission oil level is low. But for now, many cars on the road are equipped with dipsticks, so it's very easy to find out exactly how much oil your engine is using and how much you may need to add to get your engine running to its full potential.

Changing your oil regularly is a key step in keeping your engine running well, so it's a good idea to check it often to make sure there's plenty of oil lubricating the inside of the engine. Located near the front of the engine, the typical engine oil dipstick will have a t-shape or oval-shaped handle—possibly stamped with the image of a dripping oil can—attached to a flexible metal rod that slides down the dipstick tube and into oil pan. It is here where the tip of the rod meets with the oil accumulated in the bottom of an idle engine. Of course, if you were the pull the dipstick out with the engine running, hot oil can possibly spout out of the dipstick tube, spew everywhere, and potentially damage other parts in the engine bay, and, more importantly, possibly burn you.

The case is very different when checking the transmission fluid. Usually located near the rear or the front of the engine (depending on where the transmission meets the engine), the stick can typically be identified by its different color, shortness in comparison to the oil dipstick, and in some cases it might even be labeled. If you're uncertain of where it is, check your owner's manual to find its location. The engine typically needs to be warm and running in the Park or Neutral position, but it's best to check your owner's manual as some automatic transmissions require different steps.  

How do I know if my dipstick needs to be replaced?

When you remove either dipstick, you'll find markings on the tip. These markings can vary depending on the engine, but they may have a "Low"/"Full" or a "Cold"/"Hot" label to help you gauge just how much, if any, oil or transmission fluid needs to be added. Some markings may only have two dots, one to indicate "Low" and one to indicate "Full." If the markings are scratched or faded to the point where they're illegible, it may be time to replace your dipstick. The handle itself may also snap off, or, in worse cases, the dipstick itself can break.

In some vehicles, the dipstick tube is a foreboding replacement because they can be made of plastic. These dipstick tubes can crack, split, or even sever into brittle chunks. It's a good idea to keep an eye on your dipstick tube—whether it be plastic, metal, or rubber—and check it each time you check the engine oil level. This can prevent a mishap and ugly clean up if the tube were to split or crack enough to leak a noticeable amount of spillage in the engine bay.

Can I replace a dipstick myself?

The dipstick is incredibly easy to replace and won't take much more than a few minutes of your time. You just have to pull out the old dipstick and insert the new one. This process can become a lot more complicated if the dipstick handle has broken off, leaving the dipstick stuck inside. In that case, you can remove the dipstick by removing the dipstick tube and pushing it out.

The dipstick tube is a bit more tedious to remove and replace. You'll need to remove an engine cover if you have one and make sure all remnants of your old dipstick tube have been removed before applying the new one. In some vehicles, the dipstick tube might be held in place with a support bracket, which has a bolt that can be removed with a ratchet or wrench. Then twist off and pull the dipstick tube up and out with a rag to prevent any sediment from falling into the engine. Make sure you also pull up the O-ring with the dipstick tube.

Once the old dipstick tube has been removed, push the new dipstick tube into place, making sure it's nice and firm and in position with a new O-ring. Then, if you've removed a bolt, tighten it, or insert the dipstick tube back into the position it was in before you removed it.