Does Your Car Need an Oil change

FTLComm - Tisdale - Sunday, February 3, 2002

So your vehicle is running fine, it hardly seems worth the bother checking the oil when you refuel and the book says change it every 5,000 Km but like what does it matter if you go to 10,000?

Modern engines are very highly refined old technology. Fifty years ago an automobile engine was pretty much the same as we see today with the exception of the use of aluminum and plastics but essentially they use expanding heated gases to thump down the pistons and turn the crank.

Where these engines of today really differ is in quality, the tolerances of today's engines is very tight and the consequences are that these engines made in the last two decades require remarkably little maintenance. In the fifties a typical engine in any make of vehicle would go about 50,000 Km and need its head overhauled (a valve job). At 100,000 Km that same engine would be completely wore out and require a complete overhaul including piston rings, crankshaft redone, new bearings and seals.

With modern engines a top overhaul rarely occurs before the whole engine is done and that is not usually until 300,000 or more. Because of the cost of rebuilding and the value of a car with that much mileage on it most cars are traded off, scrapped or a new or newer engine from a wreck is put in its place.

This vehicle shown above is in excellent shape but its engine was worn out so the owner opted for an engine from an auto wrecker The replacement engine had low mileage and excellent compression but had almost no oil pressure at idle. Without oil pressure it would be only a short while before this engine seized. A replacement oil pump did not improve things and that meant one thing, the crankshaft bearings must be damaged. Oil is pumped through the crankshaft to lubricate each bearing that holds the shaft in place and to each piston where it connects to the crankshaft.

The former owner of this engine must have taken a fairly casual attitude toward oil changes and ran this engine with dirty oil. The grit in the oil did not damage the cylinder walls allowing the engine to have good compression but the crankshaft bearings were destroyed.

Under the warrantee from the auto wrecker the engine was getting new bearings on the crankshaft but let that be a lesson to us all. Failure to maintain an engine properly will result in excessive premature wear and early failure deep within the engine.

Preventative maintenance to your vehicle is amazingly inexpensive compared with waiting for parts to wear out and fail. This is not just true of what's under the hood but the whole machine.

Brakes are a case in point. If your vehicle is regularly inspected and service by a good shop they will spot possible trouble long before it leads to catastrophic failure. Brake pads and brake shoes are relatively inexpensive items and if they are replaced before they begin to announce their demise with squeals or vibration. A set of brake pads will cost about $60 on most vehicles about one third the cost of complete brake overhaul from worn out pads scoring the rotor disk which will require them to be turned down (put on a lath, which can only be done about once in the life of a disk) or replacement which will definitely hit your VISA or MasterCard with a resounding wallop.

When you have that simple oil change the vehicle will be inspected, exhaust system looked over, lights and electrical system checked, suspension checked, tire pressure corrected, battery cleaned up,belts checked and all other fluid levels topped up. Each of those items could leaving on the side of the road or street requiring a tow and putting your live and the lives of your passengers in danger. After all we live in a climate that is not forgiving and being stranded is a life and death matter. So that regular oil changes do far more for your car than keep the motor running. They will save you money, prolong the life of your vehicle and increase the safety and reliability of your vehicle.
Thanks to Randall Automotive for helping with the reseach for this story.