Skip the auto shop - Our mechanics make house calls

Q: Does synthetic oil cause leaks in older vehicles?

asked by on

Hi,

Following link describes that synthetic oil may cause leaks in older model vehicles.

https://www.yourmechanic.com/article/can-you-switch-between-regular-and-synthetic-motor-oil

However, myth vs fact link below addresses exactly the same question and contradicts with what YourMechanic.com explains.

http://www.pennzoil.com/en_us/education/know-your-oil/why-synthetic-oil.html

Which one is true?

Thanks for your help and time.

Opinions vary pretty widely with this topic. For the most part, if a vehicle’s engine has spent most of its life using conventional oil, it should stick with conventional oil. The full synthetic blend has more defined and uniform molecules. So where an older vehicle using conventional oil may have never had an oil leak, you may start to see oil leaks with the more defined, uniform, and "more slippery" full synthetic oil. Conventional oil may leave deposits that can, for lack of a better term, "plug" a small leak where the full synthetic oil with the better detergents will wash away these deposits and the leak becomes more prominent. An older vehicle with newly installed seals may have a good experience with full synthetic oils. If you have a newer vehicle which was engineered to use full synthetic oil, use full synthetic oils.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: 2002 Nissan Sentra GXE is smoking out the tail pipe. I replace a knock sensor and the code for the knock sensor still pops up.

HI there. There are different symptoms that create smoke that emits from the tail pipe. Here is a description of the different smoke for you to check: Smoke Types Blue: Blue smoke is an indication that the engine...

Q: Need an oil change

BMW high performance synthetic 5w40 or 5w30 or equal weight synthetic oil will be best for your car. A certified mobile mechanic from YourMechanic can do an oil change at your home or office.

Q: Car burning oil.

The BMW manufacturer considers 1 quart per 750 miles for normal engines and up to 2.5 quarts on motor sport engines. Under heavy loads the engine will use more oil. This is what BMW says is normal. You should not...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.