Q. My collector car only drives a few hundred miles per year. How often should I change the oil?
- A. Collector cars typically sit for extended periods and can be subjected to a wide temperature range. Additionally, they’re normally taken for short trips, which don’t allow the engine to reach operating temperature and evaporate accumulated moisture from condensation. For best protection, change the oil in collector cars once a year.
LEN GROOM
Technical product manager
Amsoil- A. Unfortunately, engine oil still gets contaminated while sitting in the crankcase in your garage. It collects condensation and debris and should be changed every 12 to 15 months.
MICHAEL TRUEBA
MPT Industries- A. For a collector, classic, vintage, legacy or historic street or muscle car, I recommend every 3000 miles or once a year, whichever comes first. It’s always best to change oil prior to any lengthy storage period (weeks to months) so the engine sits with fresh oil in its block. It’s never good to store a vehicle with used oil in the crankcase, as used oil contains harmful internal combustion byproducts, like acids, soot, varnish and moisture.
KENNETH M. TYGER
Director of Technical Services
Penn Grade/PennGrade1 LubricantsQ. Since modern oils are so much better, do we stick with 20W-50 in our older engines or move to a modern, lighter oil?
- A. Stick with what the OEM recommends. Your engine was designed to use a specific viscosity of motor oil. An oil that’s too thick or too thin can, for example, fail to adequately fill the clearances between the bearings, leading to wear. While modern oil technology is better, the oil’s viscosity still plays a vital role in protecting your engine.
LEN GROOM
Technical product manager
Amsoil- A. It’s always better to use an oil of the same viscosity specified by the engine manufacturer. Unless the engine is being run in an extremely cold climate, continue to use 20W-50 if that is what’s recommended.
MICHAEL TRUEBA
MPT Industries- A. The viscosity choice is a matter of bearing clearances and oil temperature. Again, keep the application in focus and not the motor oil. There isn’t a one-size-fits-all chemistry. The application always dictates the chemistry, so the choice of oil should always be made in light of the application.
LAKE SPEED JR.
Certified lubrication specialist
Driven Racing Oil- A. There is no universal answer. It’s important to consider the engine and application as well as to consult the original equipment manufacturer owner’s manual.
Viscosity is a very important parameter of a motor oil. Some modern engine manufacturers recommend 0W-grade motor oil products, even in high-output systems. These engines have been engineered for low-viscosity oils, generally to help deliver either more power or better fuel economy.
An older engine may have specific requirements driving the use of a heavier oil, so it’s important to follow the OEM’s motor oil specifications. For modified or custom engines, the modifications made and the expected use should guide the selection of the engine oil viscosity.
In instances like this, it’s beneficial to understand what the SAE J300 designation specifies for multi-grade engine oils. Take 20W-50, for instance: 20W is the oil’s “winter grade,” with the 20 representing its viscosity under cold operating conditions. The 50 is its “summer grade” and specifies its viscosity under hot operating conditions.
Another example: A 0W-40 and a 10W-40 oil have comparable performance at higher temperatures, but the 0W product would perform much better in cold conditions.
Determining whether you can switch to a different grade of motor oil requires taking a detailed look at your vehicle handbook and consulting any service advisories that your OEM may have issued. If your engine is modified, you should also seek your engineer’s advice and consider your desire to experiment.
ERIC W. KALBERER, PH.D.
Global product application specialist
Pennzoil
RICHARD DIXON
Technology manager
PennzoilQ. Which is better for my original, older engine and why: conventional oil or synthetic? And which one leaks less? And what if that older engine has been recently rebuilt?
- A. As long as your engine is mechanically sound, a motor oil isn’t going to cause leaks–whether it’s conventional or synthetic. If it’s leak-free and in good shape, use a synthetic oil to provide maximum protection. The same goes for healthy rebuilt engines.
If your engine is older and does leak, the problem could be seals and gaskets that have become brittle or worn. Even if the engine doesn’t leak, those seals could still be in poor condition. Sometimes sludge builds up enough to effectively prevent oil from slipping past deteriorated seals or gaskets.
Using a high-quality synthetic oil with good detergency can dissolve that sludge and reveal the true condition of the seals, causing leaks. If you suspect your engine falls into this category, we recommend sticking with a conventional oil.
LEN GROOM
Technical product manager
Amsoil- A. In most cases, classic engines that have been using conventional oil for several years should stay with conventional oil. The seals get accustomed to the lubricant, and big changes (like switching from conventional to synthetic) can cause them to leak. For rarely driven cars, the risk is not worth the reward, so just stick with conventional oil. Now, if the engine is getting rebuilt, then you can go with synthetic (and then stay with synthetic) after the breaking-in process.
LAKE SPEED JR.
Certified lubrication specialist
Driven Racing OilQ. Is there anything to these oils aimed at high-mileage and older cars, or this just a marketing gimmick?
- A. Many high-mileage or vintage-car oils have higher amounts of zinc, which does help decrease wear in older engines. Their additive packages also include the detergents and dispersants needed to help clean and protect your engine, along with seal conditioners and more. Of course, with these products you also have a lot of marketing noise and false promises–as you do in any other segment–but quality high-mileage oils are certainly good for your classic or vintage car.
Remember to be specific and differentiate between oils for high-mileage cars and classic or vintage cars. There are many different high-mileage oils, but a 2009 Audi diesel with 200,000 miles will need a different motor oil than a car from the ’70s.
OLE WAGENBACH
Rowe Motor Oil- A. I strongly believe that a legacy stock engine should use an engine oil formulation that was more prevalent in the earlier era–certainly one that is conventional or mineral-based and possesses higher antiwear content. I have never been a fan of running modern-day, full-synthetic engine oils in older engines. Due to their light nature, synthetic oils could exacerbate any leaking, blow-by or oil burning issues. If your engine has been rebuilt and the system is without a catalytic converter, reach for oil laden with antiwear additives.
KENNETH M. TYGER
Director of Technical Services
Penn Grade/PennGrade1 LubricantsQ. What is an acceptable max oil temperature?
- A. Once again, this will depend on the design of the engine. Turbocharged engines usually run much hotter–sometimes 250 to 300 degrees Fahrenheit. Generally, oil should stay in the range of 220 to 260 degrees. Temperatures above that may raise evaporation loss and shear issues.
MICHAEL TRUEBA
MPT IndustriesQ. What is this talk about seal-swell additives? What are they, and is it all just marketing speak?
- A. In the early days of synthetic oils (back when they were polyalphaolefin-based) seal shrinkage was commonplace, which means leaky engines were, too. Today, formulators use additives or ester base stocks to counterbalance seal shrinkage issues, so leaks are no longer a concern.
MICHAEL TRUEBA
MPT Industries- A. Seal-swell additives are seal softeners, or conditioners. They can clean seals and swell them slightly by replacing elastomer molecules or nitrile atoms that they’ve lost to wear, oxidation and sludge. In other words, seal-swell additives can help stop and prevent leaks.
LEN GROOM
Technical product manager
AmsoilQ. Once I move to an oil with seal-swell additives, can I go back to an oil without them?
- A. Technically, yes, but it would not be wise, particularly after the reconditioning of seals.
KENNETH M. TYGER
Director of Technical Services
Penn Grade/PennGrade1 Lubricants