How to: know if you have a blown head gasket
 

The head gasket on a truck performs two important functions. First, it contains the internal combustion process; second, it separates the coolant from the oil as they work their way independently from the engine block to the truck's cylinder head. The head gasket is located between a truck's engine block and its cylinder head, making it difficult to access; this is why replacing one can be so expensive. There are many different signs indicating a blown head gasket; keeping them in mind and acting on them quickly is the best way to prevent major motor damage to your vehicle.

Bubbles In the Radiator
If you suspect that your truck has a blown head gasket, checking its radiator is one way to confirm it. When a car's head gasket has a leak, air bubbles can travel into the radiator. To check this, remove the trucks radiator cap. After letting the engine warm up, rev it a couple of times; if bubbles emerge from the radiator, you probably have a blown head gasket.

Exhaust Symptoms

Unusually white smoke may be emitted from the tailpipe. The trucks exhaust may have an unusually sweet smell when there is a problem with its head gasket.

Oil Symptoms
A trucks oil can help diagnose a blown head gasket. Oil becomes contaminated when a head gasket has a leak or other problems. When the oil becomes contaminated, a milky looking ring will appear around the oil cap. This ring occurs when coolant mixes with engine oil.

Engine Symptoms
A slow, sluggish or unresponsive engine is another sign of a blown head gasket. This happens due to the compression loss which occurs when a head gasket has a leak, tear or other problem. A vehicle is much likelier to overheat under these circumstances as well.

Spark Plug Symptoms
For vehicles that use green coolant, the spark plugs may provide another symptom of a blown head gasket. In this case, the plugs may have a green tint around them. In extremely severe cases, coolant might even spray out of the spark plug holes.