Synthetic oil can last longer than conventional oil, but how much longer? Some shops try to sell you on short oil change intervals, manufacturers extend it, and car enthusiasts find a thousand different answers.
But what is the right answer? Below is what experts recommend when it comes to synthetic oil change intervals to ensure your engine is happy.
Average Synthetic Oil Change Interval
With synthetic oils, the change intervals are often about 5,000-10,000 miles, depending on the type of engine and synthetic oil blend being used.
Typically, this is much higher than “normal” conventional oil change intervals of 3,000-5,000 miles, so to be able to go 5,000-10,000 miles (depending on oil type) before needing an oil change can be a very attractive possibility.
Synthetic oils (and synthetic blends to an extent) can also have other advantages for a vehicle’s engine, like improved performance overall, and much less sludge and deposits that are left, which are present with conventional motor/oil blends – but the costs are higher as well.
If you look for the best prices on motor oil, the loss may not be too great.
The best way to know what your particular car/truck’s oil change interval is to check your vehicle’s manual for what the manufacturer recommends (including the type of oil).
Also, if you do a lot of starting and stopping, you may even want to have your oil changed sooner than recommended.
When Your Synthetic Oil Change Interval Should Be Lower Than Average
There are certain scenarios for specific driving conditions that can make the synthetic oil change interval lower than it would be in average driving conditions.
For example, if a vehicle owner is someone who likes to take their car or truck into off road terrain, or drive on dirt and gravel roads, those conditions can require a more frequent synthetic oil change interval.
Some other scenarios that could make the synthetic change interval a little lower than normal are regularly towing a trailer or some other type of load, excessive idling, or just not driving enough. Engine oil can expire after a certain amount of time.
People might not realize that idling an engine for a long period of time can require anyone to have to change the synthetic oil more frequently.
Another condition that can make the oil change interval less than average is if a driver is frequently doing short trips when the outside temperature is below freezing.
What Are the Consequences of Ignoring Recommended Oil Change Intervals?
Here are the possible consequences of exceeding the manufacturer’s recommendation for oil changes for synthetic oil:
- Oil Breakdown – Synthetic oils show better resistance to breakdown than conventional oils, but can nonetheless become degraded based on time and use. Exceeding the manufacturer’s recommended oil change interval poses a risk of allowing additional contamination buildup and oxidation, decreasing the oil’s lubrication and protection for the engine.
- Sludge Buildup – Oil byproducts and contaminants can form sludge over time. Excessive amounts of sludge can clog small engine passages and stick to components, which can dramatically decrease engine performance and life. More oil changes improve and limit sludge.
- Voided Warranty – Many manufacturers have the expectation of reasonably following change intervals, and if you exceed these intervals, it could void your warranty if the engine fails.
- Reduced Fuel Economy – The degradation of oil causes it to become thicker and dirtier, which causes additional friction and drag. This results in slightly reduced fuel economy. Regularly refreshing your oils maintains better fuel economy within the engine.
- Engine Wear – An important benefit of synthetic oil is offering exceptional lubrication and protection from engine wear. Once the oil change is exceeded, the wear protection is beginning to be less of a factor as the oil breaks out, leading to faster wear of bearings, cylinder walls, camshafts, etc.
- Oil Leaks – Oil can become dirtier and more acidic, and subsequently can corrode seals and gaskets over more extended period. This could then result in possible leaks if the seal/gasket became weak. Renewed oil allows better-maintained gaskets and has lower leakage potential.
Is Synthetic Oil Really Worth the Cost?
Synthetic oil is worth the price for most vehicles (if not all). Here are some reasons why:
First, synthetic oils are more highly refined, less prone to breakdown under stress, and more stable than regular oils. They are based on very pure base oils and special additives that help resist breakdown depending on heat and driving conditions.
Synthetics also have a tighter molecular structure, making them less susceptible to thickening at extremely low temperatures.
Synthetics’ superior stability can help retain viscosity, lubricating strength, and ingredient protection for much longer drain intervals of oil, usually around 7500+ miles with most modern synthetics.
The enhanced lubrication, cooling, and cleaning properties of synthetic oils provide superior protection of critical engine parts while creating less wear and tear over the 7500+ miles.
The savings in reducing engine wear could mean reduced service costs and an increased engine lifespan when compared to standard conventional oils.
Longer service intervals can be followed with synthetic oils. A synthetic drain interval could then save time and money on maintenance due to fewer oil changes.
Some synthetic oils can raise fuel efficiency slightly since the lower viscosity results in less resistance and friction in the engine. The ability to reach peak performance earlier and keep it for longer could translate to operational and efficiency improvements.
In many cases, while you may pay more up front for a synthetic oil, the stability and durability will outweigh the cost over time, and this can help you to see the value in using a full synthetic throughout its life cycle.
This is particularly true for modern high-performance, turbocharged, or heavy-duty engines that lean more towards high-quality synthetics to keep their engines operating.