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Vehicles that have traveled 100k or more miles have endured a lot of road wear and have been running for thousands of hours. With all that work comes the possibility of engine wear and damage to the car’s critical components. So, drivers are wondering if it is a logical decision to switch to synthetic oil at 100k or higher mileage.
Switching to synthetic oil is a great way to extend your engine’s life and get longer oil change intervals. There are so many advantages to benefit from once you switch to synthetic oil regardless of your engine mileage. However, there are some variables you should look out for. Keep reading to find out!
Factors To Consider Before Switching To Synthetic Oil At 100k
There is a common argument that is rooted in the belief that synthetic oil reacts poorly with the seals of a high mileage car engine. So, many drivers doubt if changing their car oil to synthetic is logical or not after they have 100k or more miles on their engines.
With so many opinions floating all around, you must be baffled and wondering which one is true. We’re here to help you by digging out the truth about switching to synthetic oils in high-mileage cars. But, first, we need to discuss all the factors that affect it to get a better understanding of the problem at hand.
1. Check The Seals And Gaskets
Switching to synthetic oil is quite popular these days because it extends your engine’s life. However, if your car is leaking, you might need to reconsider. Since synthetic oil is a low viscosity oil, it will only worsen the situation. Also, if your vehicle’s engine uses old rope-type oil seals in addition to cork gaskets, then switching to synthetic oil is a NO NO! Otherwise, the full synthetic oil will leak past the older seal types and gaskets.
2. Leaking Problem
Some people have reported that there could be a leaking problem. If you are running your vehicle on conventional oil, then first check if the oil tends to cake up near the seals. In case, you put synthetic oil on this location, it will clean up everything including the caking that could cause a leak in the seals.
The conventional oil can leave varnish and sludge behind. Since the synthetic oil has detergents added, it will remove much of the gunk left by the old oil. So, initially, you should go for frequent oil change intervals and then, you can move to the longer drain intervals.
Check your car for any prior leaks and make the required repairs or replacements before switching to synthetic oils.
3. Synthetic Oil’s Texture
What happens is that all molecules of synthetic oil are of the same size. On the other hand, with regular or conventional oils, every molecule is of a different size. This is why synthetic oils are said to be slicker or runnier. Since the older and high-mileage cars have gaps between their seals and gaskets, the synthetic oil molecules will be small enough to pass through these gaps. This would result in leaks that weren’t visible earlier because the larger molecules of regular oil would fill and clog the gaps.
We recommend that before the first switch to synthetic oil, you should immediately repair, clean with a gentle cleanser, polish the engine if it has a build-up of sludge. Otherwise, the detergents in the synthetic oil will clear the sludge in the engine exposing the gaps and start leaking out through them. This is to make sure that the gaps are taken care of before changing the oil to a synthetic one.
Switching To Synthetic Oil At 100k – Is It Logical?
It’s never too late to switch from conventional oils to synthetic oil. It offers a better coating on the metal surface. Hence, there will be lesser friction, lower heat generation, and as result lesser wear and tear. This leads to somewhat less horsepower being wasted in the operation of the car engine. This, in turn, provides better fuel economy and allows you to drive at greater torque even at a low RPM.
Moreover, the risk can be lessened if you stick to shorter initial synthetic oil changes (around 3000 to 5000 miles) and using good oil filters. The synthetic oil can indeed handle longer intervals but this is to allow a little bit of engine cleaning. Also, the synthetic oil will leak more in the initial oil changes but the leaks will seal up within a couple of oil changes.
However, these days new kinds of high-performance synthetic oil have been introduced. These are meant to be used with high mileage vehicles with 100k or more miles on their engines. To overcome the leak problem, it has a special formula that stops leaks, resists oil breakdown, and keeps sludge at bay. That is enough to argue that you can indeed change to synthetic oil even at 100k.
Note: Spend your money on a good synthetic oil and also get a quality oil filter. This is because the very first thing that causes oil issues is dirt getting into the oil. So, the quality of the oil filter you use can make a massive difference to keep the gunk out of your oil.
By now, you must have understood that switching to synthetic oil at any mileage is a good decision if you stay cautious around a few points. If your car is in good working condition and is regularly maintained, synthetic oil will protect the engine and make it more efficient. However, to avoid problems you should clean up the engine (engine flush) before the oil change and go for shorter oil change intervals at first with synthetic oil.
This will clean up the deposited debris and close the leaks. If you want to be more sure about the switch, perform oil analysis on your car engine. Also, make sure you don’t put in regular or conventional oil back in once you start with synthetic oil.