01 / THE JOB
What oil does and why it quits
Oil holds a microscopic film between metal parts moving at thousands of RPM, carries combustion heat away, and suspends the byproducts of burning fuel so they drain out instead of settling in.
It quits for two reasons that have nothing to do with the base stock ads argue about. Its additives deplete: detergents fill up with soot, anti-wear compounds get consumed, acid neutralizers exhaust. And it gets contaminated: unburned fuel, condensation from short trips, and fine particles the filter cannot catch.
Synthetic base stock resists heat breakdown and flows better cold, which is why it earns longer intervals. But additives deplete in synthetic too, which is why 10,000 miles is a ceiling and not a floor for stretching. The interval was never really about the oil wearing out; it is about the oil filling up with the job it did.
02 / WARNING SIGNS
Signs the oil is overdue
Color alone means little on diesels and direct injection, but grit or a burnt smell means overdue.
Valvetrain clatter that fades as pressure builds points at tired oil or a low level.
Consumption is its own problem. Check monthly; a quart per 1,500 miles deserves attention.
Any oil light at operating temperature is a stop-now event, not a soon event.
The dipstick habit outranks the interval debate. Most oil-related engine failures start with a low level nobody checked, not an interval missed by a thousand miles.
03 / INTERVAL RANGE
Modern intervals and the severe footnote
Factory intervals converged in the 2010s: full synthetic, 7,500 to 10,000 miles under normal conditions, roughly half under severe. The definition of severe is where the real answer hides.
| Situation | Typical range | What to do |
|---|---|---|
| Modern schedule, normal use | 7,500 to 10,000 mi / 12 mo | Toyota, Ford, FCA at the top end |
| Severe conditions | 3,750 to 5,000 mi / 6 mo | Short trips, towing, dust, idling, heat |
| Subaru schedule | 6,000 mi / 6 mo | One of the shorter modern clocks |
| Oil life monitor vehicles | Follow the monitor | With the published ceiling as the limit |
| Turbo engines, short winter trips | Toward the severe end | Fuel dilution is the quiet enemy |
Read the severe list honestly: repeated trips under five miles, extended idling, stop-and-go heat, dusty roads, towing, sub-freezing starts. That is not an edge case; that is an average American commute in an average winter. When in doubt, you are severe.
04 / YOUR VEHICLE
Find the interval for your car
The table below shows how the published figure moves across vehicles we cover. Each link opens the full schedule for that year.
| Vehicle | Published interval |
|---|---|
| 2017 Chevrolet Equinox | 7,500 mi / 12 mo |
| 2017 Chevrolet Silverado 1500 | 7,500 mi / 12 mo |
| 2017 Ford Escape | 10,000 mi / 12 mo |
| 2017 Ford F-150 | 10,000 mi / 12 mo |
| 2017 Honda Accord | 7,500 mi / 12 mo |
| 2017 Honda Civic | 7,500 mi / 12 mo |
| 2017 Honda CR-V | 7,500 mi / 12 mo |
| 2017 Jeep Grand Cherokee | 10,000 mi / 12 mo |
| 2017 Jeep Wrangler | 10,000 mi / 12 mo |
| 2017 Nissan Altima | 7,500 mi / 12 mo |
| 2017 Nissan Rogue | 7,500 mi / 12 mo |
| 2017 Ram 1500 | 10,000 mi / 12 mo |
Vehicle intake
Find your schedule
The VIN is usually visible at the base of the windshield.
Sources and review dates appear on every schedule.
05 / DIY OR SHOP
The classic entry-level job
An oil change asks for a drain plug, a filter, and cleanup. It remains the standard first DIY job, and also the one where quick-lube pricing is competitive enough that many DIYers retire from it.
Warm engine, drain fully, new washer on the plug, filter gasket oiled and hand-tight plus a turn, exact quantity and grade from the manual, level checked twice. Keep the receipt; it is your warranty paper trail.
Fast and cheap at any competent shop. Specify the correct grade in writing; thin 0W-16 and 0W-20 engines have been mis-filled with bulk 5W-30 at busy counters.
06 / COST BREAKDOWN
What oil service costs
07 / IF YOU WAIT
How overdue oil kills engines
Overdue oil fails engines in slow motion. Depleted detergents let deposits bake onto hot surfaces. Sludge thickens in the pickup screen and oil passages, starving the farthest bearings a little at every cold start. Variable valve timing systems, which run on oil pressure through fine passages, act up first on many modern engines, setting codes that get diagnosed as sensor problems.
By the time symptoms are audible, the wear is done and the remedies are mechanical, not chemical. No engine flush un-wears a bearing. Against that arc, the modern interval is a bargain: two changes a year, roughly the cost of a tank of gas each, for the one fluid every moving part in the engine shares.
08 / QUESTIONS
What owners ask
Is synthetic oil worth it on an older engine?
If the manual allows conventional, either works at the conventional interval. Synthetic resists heat breakdown and cold-start thickening better, which is why every modern schedule assumes it. Switching an old engine to synthetic is safe; the flushing-out-sludge horror stories date to formulations decades gone.
What does the oil life monitor actually measure?
Most compute oil life from engine revolutions, temperatures, and trip patterns rather than sampling the oil. GM and Ford's systems are algorithmic. They are good at matching the interval to your real driving, which is the entire point of severe-service schedules.
Can I stretch a 10,000-mile interval further with premium oil?
The interval belongs to the engine, not the bottle. Extended-drain oils exist, but warranties and engine tolerances were validated at the published interval. Stretching it saves perhaps forty dollars a year against an engine.
Does short-trip driving really count as severe?
Yes, and it is the most common severe condition of all. Trips too short to fully warm the oil leave condensation and fuel in the crankcase, which is harder on oil than highway miles. A five-mile commute is severe service.
Why does my new car use 0W-16 or 0W-20 oil?
Thinner oils cut friction for fuel economy, and modern bearing clearances are designed around them. Using an older, thicker grade because it feels more protective works against the design. Use the grade on the oil cap.
09 / SOURCES
Where to confirm the interval
- 01
The maintenance schedule supplied for your exact model year and engine.
- 02
The owner's manual section covering maintenance and severe-use conditions.
- 03
Service records showing the date, mileage, and parts used at the last service.