Until recent innovations in automotive production and lubrication came along, the break in process for new car engines was rather tedious, and best adhered to closely. Vehicle speeds were to be restricted upon initial operation, with higher speeds allowed as the miles stacked up. Oil changes were recommended at close intervals, with the first to occur as early as a hundred miles, by some preferences. Certain break in rituals are still in order, and vary by make and model, but manufacturers typically perform no actual break-in services on new car engines.
There are steps taken at some factories to ensure engine designs and assembly techniques are successful. Manufacturers may pull a random engine off the assembly line for testing purposes. A representative mill might be connected to a dynamometer, and run through various operating ranges to check for defects. Horsepower and torque measurements are expected to reach certain parameters, and any failures or shortfalls could prompt investigations or stoppages. Other quality assurance techniques involve actual road tests. New cars and trucks arriving at dealerships with a few hundred miles on the clock may be accompanied by a factory- endorsed recount of the process. Some manufacturers perform an engine tear-down after a road test, to aid research and development.
Some of the manufacturer recommendations for new car break in may seem like plain old common sense, while others require an appreciation for mechanics unshared by most consumers. Lead-foot throttle operations, or towing chores might never cross the mind of a conscientious new-car owner, and rightly so. However, damage can be done in more subtle and seemingly safe usage. Extended idling, or rock-steady cruising speeds, can prevent the piston rings from burnishing the cylinder walls properly. Laying off the cruise-control button may be frustrating for a gadget-proud owner, but such precautions can be disregarded as soon as a thousand miles shows up on the odometer, in most cases.
The initial oil change for a new car may be more crucial than some manufacturers are willing to admit. While synthetic oil usually allows extended service intervals, it may be a wise move to ignore optimistic forecasts for oil service life in a new engine. Industrial-grade engines, and small air-cooled mills, like those in lawn mowers and motorcycles, often have their first oil change after only a few hours of operation. This is done to prevent errant minute particles from being mashed into relatively soft bearing surfaces, or scraped against cylinder walls, and typically results in engine longevity. The same attentions paid to a new car engine, could guarantee a quality and longevity not shared by less fortunate engines of the same year and make.
Following manufacturer recommendations to the letter can ensure the validity of a warranty, should the dealership or factory zone representative attempt to disallow a claim. However, more diligent care could provide a level of performance and quality that surpasses vehicles subjected to average, or minimal, attentions. Proper performance and longevity not only add to the resale value of any particular make and model, but might erase any urgent needs to trade the old pony in for a new mount. The pride and satisfaction an owner feels from keeping the old horse in fine fettle could overshadow any joy derived from acquiring a new ride, and a new auto loan.
