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How to check a used car for oil and transmission fluid leaks

How to check a used car for oil and transmission fluid leaks

It is always exciting when purchasing a car whether the car is new or used. When purchasing a used car; it is important to take extra measures to make sure you are getting a dependable vehicle that will not fail on the road. Engine oil and transmission fluid are what helps lubricate components in the engine and transmission. Without properly oil or fluid levels; it can lead to catastrophe. Here are some of the steps to take to check for leaks when inspecting a used vehicle.

First, get yourself a good flashlight, floor jack, jack stand, shop rag, and mechanic or latex gloves. When inspecting an engine or transmission for possible leaks; always conduct a visual inspection. It will give you the impression whether the vehicle has been taken care properly. Start by opening the hood. Use a flashlight and shine on the engine, if the engine cover is on the way, remove it for better visual. Remove the engine dip stick and check the oil level and oil color. The oil level should be on the full level. If the engine oil is on low or below the low level; it is possible that there may be a leak.

Check the valve cover area which is located on top of the engine. There should be no leaks, or dirt accumulated on the valve cover seal, if there is, that is a sign that it has been leaking. Usually, when the valve cover has been leaking, engine oil leaks from the top of the engine to the bottom. The good news is that it is not expensive to repair. If you are handy and mechanical inclined you may be able to replace the valve cover gasket yourself.

Next, check the bottom the engine. There are a few areas you will want to check. Ask the seller permission if you can lift the vehicle and place it on jack stand. Check the engine oil pan gasket for possible leaks. If there is a leak present, the gasket will be full of dirt and oil. In addition, check the engine drain plug for possible leaks. Sometime, when a drain plug is removed after many oil changes, the threads start to wear. This will allow engine oil to seep through. Next, check between the engine and transmission for possible leaky rear main seal. Usually when a rear main seal is severely, it will leak very fast.

Next, check the crankshaft pulley for possible leaks. Behind the crankshaft pulley is the front main seal or crankshaft seal. This area can also leak due to high mileage and wear and tear. Next, if the vehicle is timing chain driven check around the timing chain cover; It is possible it can leak due to high mileage or simply worn seals. Furthermore, if the vehicle is timing belt driven; you will want to check below the timing cover for possible leaks. Two things will cause a leak. One is a bad camshaft seal and secondly a bad crankshaft seal. In addition, check around the oil pressure sensor for leaks and engine that is equipped with solenoids.

Now the engine has been inspected for possible oil leaks, it is time to check the transmission. Check the transmission pan for possible leaks. Dirt will accumulate around the transmission gasket if there is a leak. Moreover, around the shift solenoid and transmission drain plug for possible leaks and lastly check around the axle seals. Transmission fluid can leak in that area if the axle seals are worn.

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