I've read a lot about changing the coolant in our cars, and that it needs to be done at a 5year interval. What I did't know is that there is an easy way to check your coolant to see if it really does need to be changed. I haven't changed mine on my 08 redline yet so I tested today and it is still fine but I will change it in the spring. The test is easy to do just loosen the coolant cap and start the car to let it get to normal operating temp. use a volt meter set to 20 volt dc and put the positive probe in the coolant and the negative probe to the negative side of the battery if you have less than .04 volts your coolant is fine mine showed .02-.03 that's why I will change it in the spring.The car has just under 24k on it. Just putting that info. out there in case anyone is interested.