Does engine oil get thinner over time?

I was draining old oil from my engine and it appeared very thick and dark. I assumed older engine oil would get thinner as it aged, so I was confused by how viscous the oil was. Is engine oil supposed to get thinner over time?

Find out if you’re getting ripped off on your car insurance in less than two minutes.
No spam · No long forms · No fees
Find savings (100% Free)
rating white
3.5k Ratings
Answer provided by
Kara Vanderbeek
Answered on May 03, 2022
While many people assume that oil gets thinner after extended periods, the opposite is true!
Engine oil actually becomes thicker over time as a result of oxidation.
Depending on such factors as the temperature, moisture, oxygen levels, engine condition, and catalytic reactions, the oil will oxidize at a specific rate. As a result, the oil will become thicker and darker.
While this is a natural process in engine oil, it’s still important to have your oil changed on a regular basis to ensure the optimum performance of your vehicle.
As you take care of your engine’s oil, make sure you have a good car insurance policy with Jerry.
A licensed broker, Jerry does all the hard work of finding cheap quotes from the top name-brand insurance companies and buying new car insurance. Jerry will even help you cancel your old policy.
And to ensure you always have the lowest rate, Jerry will send you new quotes every time your policy comes up for renewal, so you’re always getting the coverage you want at the best price. This level of service is why Jerry earned a 4.6/5 rating on the App Store and made it the top insurance app in the country.

Here to save on car and home insurance? Great, you do that. We’ll do everything else.

Sign up in under a minute.
No need to fill out forms or shop around. Sign up in 45 seconds to start saving. Jerry does the rest.
Jerry collects and analyzes your current coverage.
Say hello to Jerry, your new insurance agent. We’ll contact your insurance company, review your current plan, then find the coverage that fits your needs and saves you money.
Get the best options before your renewal.
Jerry does all the picky, busy work by comparing prices and coverage from more than 50+ insurance companies. We compare what we find to your current policy and offer you the three best options before every renewal.

Easiest way to compare and buy car insurance

No long forms
No spam or unwanted phone calls
Quotes from top insurance companies
Find insurance savings — it's 100% free