Actually, it isn't. Since I was checking the condition of the coolant on the SSGT on a regularly scheduled task, I was verifying the quality of the coolant and its capability to provide protection to determine whether it required changing. I also visually inspected all the hoses, thermostat housing & water pump to see if any signs of coolant leakage was occurring. The only risk was the inability to inspect the thermostat, but if the coolant condition is known, a thermostat failure is a low risk. And most thermostat failures in today's cars occur in the "open state", which means the car's operating temperature remains lower than normal. (Note: I have had a thermostat fail "closed" and that was a major issue as the car overheated!) A true PM should only be an inspection task.

Now most of us change our oil & filter as a PM. But if it were economical and convenient, we'd be checking the condition of the oil using oil analysis. The results from that PM would determine whether the oil and/or filter needed changing. And that test would most likely indicate that only the filter required changing; the oil would typically be fine for at least another PM cycle. That's what large vehicle fleet's do to pinpoint when an oil change is required. Even on our Crossfires, the FSS monitors oil quality along with driving style to identify when an oil change is required. Based on how I use & drive my Crossfire, FSS tells me to change the oil/filter about every 24 months. That's when I perform the maintenance.

Nearly all Owners Manuals and Service Manuals state a "recommended" service interval for fluid flushes and systems cleanings. And I am guilty of adhering to these "recommended" services because it's more economical to execute that maintenance than rebuild/replace a major component or system! With the quality of motor oils present-day, performing an oil change by the "old standard" of every 5000 miles or 6 months is unnecessary maintenance. But the car manufacturers continue to operate that way. My 2012 Ford Fiesta clearly states in the Owner's manual that an oil change is recommended every 7500 miles using Motorcraft Synthetic Blend. But the local dealer always states to perform the maintenance every 5000 miles or 6 months. Dealer tells me that this is "preferred" maintenance to prevent the risk of serious engine damage but, in actuality, the dealer doesn't want to reduce Service Dept revenue! Imagine the financial impact if everyone started bringing their vehicles in for an oil change every 7500 miles instead of at 5000 mile intervals!