Vehicle maintenance can be very confusing. Every day, vehicles end up in junk yards because of a lack of it. At the same time, millions of dollars are wasted every year on useless services or worse, things that actually create problems.
There is only one reason to do maintenance, it is less expensive than not doing it
True maintenance prevents repair
Repair addresses a problem that has occurred
Proper maintenance is a service that prevents or lessens the chances of a more expensive repair. A major part of the problem is a misunderstanding about what proper maintenance is. Charlatans use this misunderstanding to sell all sorts of high-profit snake oil.
For instance, cleaning injectors is NOT maintenance. It is a seldom needed repair to address a specific problem, dirty injectors. Quality gasoline contains detergent and fuel injectors are designed to be self-cleaning. Routine injector cleaning will not increase fuel mileage, will not prevent problems and may cause damage. Yet it is sold everyday as maintenance. Right in the same class is induction cleaning which is only an upsell used to increase profit.
The transmission flush is a different twist. It takes an actual maintenance item, proper transmission service and turns it into a high-profit wallet flush. With a flush, clean fluid is circulated through a dirty transmission and called a service. This does not address the more problem of a restricted filter, and can make it worse.
Proper transmission service includes inspection of the unit, removing the pan on transmissions that have one, and replacing filters that are replaceable. It also provide an opportunity to torque valve body bolts, adjust bands and detect problems that may not have gotten serious yet. The fluid is then replaced with the proper fluid, specified by the manufacturer.
When Should I Do Maintenance
Modern vehicles are designed to isolate the driver from symptoms. The first symptom will often be a breakdown. Maintenance should be performed based on time, mileage and inspection. An annual general inspection, by a trusted professional will provide over all lowest cost of vehicle ownership.
The High Cost of Run Till Fail
Waiting for symptoms to occur is known as - Run Till Fail - It is the most expensive way to operate the vehicle.
By the time symptoms are noticed, damage has already been done. For instance, when a coolant light comes on, the coolant is low. This means a leak has developed, normally because corrosion has caused extensive damage to the cooling system.
Replacing the coolant based on time and specific testing can prevent thousands of dollars in repair. Waiting for a symptom is very expensive.
A check engine light, an engine running rough or using more fuel is a sign the engine management system has failed. For example, if spark plugs are not replaced [maintenance,] the secondary ignition can be over-worked. Exceeding duty-cycle can result in a coil that burns out or a module that fails. The check engine light signals the failure, after it has occurred. Replacing the spark plugs can prevent these expensive repairs.
Oil changes are also maintenance. When the oil and filter are replaced, damage causing contaminants are removed from the engine. Waiting for an oil leak, knocking noise or oil warning light, often means a new engine.
Run till fail
Value after failure (120,000 miles)
Cost for 240,000 miles (excluding finance charges, additional insurance and sales tax on new vehicle.)
Below is a short, partial list of true maintenance items