Engine oil leaks can leave a filthy mess on your driveway, but they can be eliminated for a price. That price can vary, depending on the location of the leak.
Here is a good way to figure out if your leak truly is engine oil. Put a piece of paper under the leak and let it sit overnight. Then look at the color of the fluid on the paper. If it’s dark brown, that’s going to be engine oil. If it’s red, that’s going to be transmission or power steering fluid and if it’s more of a watery looking fluid, that’s going to be antifreeze. If it’s all three of those, that’s going to be expensive!
Here are some of the main causes of oil leaks, starting at the top of the engine:
Valve covers have gaskets underneath them that can wear out and start to leak. Sometimes the gaskets are not that expensive to replace because the valve cover is accessible and fairly easy to take off. Anytime that you have an oil leak up high on the engine the oil can drip down on the hot exhaust and that’s when you get a burning oil smell.
There are rubber seals on engines as well and many times they are buried behind other engine parts such as a timing cover. These types of leaks can be pretty expensive to repair because of how much labor is involved to get to the seals.
There is also a part called a rear main seal and it is placed at the end of the crankshaft on the engine. The mechanic usually needs to pull the transmission to get to the seal, so as you can imagine that repair is going to cost a lot of money.
The oil drain plug can leak sometimes, but that’s usually a pretty easy fix. There is usually a gasket on the plug and most times replacing it solves the problem.
Sometimes the oil filter can leak oil, either because it wasn’t installed properly or it worked loose. This can be an easy fix as well and might just take a little twist to tighten the filter and get rid of the leak.
Oil pressure sending units monitor engine oil pressure and they are notorious leakers. The good news is that these are usually pretty easy (and inexpensive) to replace.
The oil pan is on the bottom of the engine and there is a gasket between it and the engine. Replacing the gasket might be fairly inexpensive to do as long as the oil pan is out in the open. But if the pan is stuck behind a cross member or the exhaust on the vehicle, it can be expensive to replace because of the additional labor required to get the pan off of the vehicle.
As you can see, there are a lot of possibilities for leaks. The best way to find out where yours is coming from is to have your mechanic take a peek at your leak.