Should I Use Synthetic Oil in Older Vehicles in Winter?

The National Weather Service is predicting that the Southwest will have warmer winter weather than usual this year, but northern states are likely to have a colder and wetter winter than average. It isn’t “just Alaska” that gets below zero temperatures for weeks on end: at least 12 other states also have below-zero average winter temperatures.

Whether or not it’s freezing outside, an engine is “cold” if the car has sat overnight, including in your garage. While the engine is getting cold, so is its oil.

When it comes time to start a cold engine, thick oil has a hard time moving through the engine. This can leave vital operating parts without lubrication – bad for vehicles of any age, but especially bad for older and classic cars. Combined with potential cold-weather battery problems, having the wrong type of oil in your older car could make it almost impossible to start in winter.

Synthetic Vs. Conventional Oil

Oil isn’t exactly like pancake syrup, but it behaves like it in cold temperatures. You know that warm pancake syrup pours easily, but try freezing the sweet liquid – it won’t freeze, but it thickens. Motor oil behaves similarly unless it is formulated like AMSOIL’s synthetic motor oil. Conventional motor oil has paraffins in it that will thicken enough to potentially keep the crankshaft from turning quickly enough to start the car.

AMSOIL cooled conventional 5W-30 oil and its Signature Series 5W-30 oil to -40ºF/C and compared how each oil poured out of a beaker. The Signature Series poured out quickly, while the conventional oil barely moved. Thick conventional oil in an older vehicle affects many systems throughout your car. The technical term for the problem is “oil starvation,” and it can lead to excessive wear and early failure of engine components.

Testing Oil Viscosity in the Cold

AMSOIL conducts tests to determine how well its oil will perform under different conditions. The Cold Crank Simulator (CCS) viscosity test measures how well an engine can turn over in cold weather. This test shows that thicker oil creates slower engine speeds than thinner oil with a better ability to lubricate and flow. When tested at temperatures well below freezing, AMSOIL’s Signature Series 5W-30 Synthetic Motor Oil had by far the lowest viscosity when compared to 9 other synthetic brands.

Use Oil With A Low Pour Point

The easiest way to know if you’ve chosen synthetic oil that’s right for your older car in winter is to look at the oil’s pour point. This number will appear on the oil’s data bulletin. AMSOIL’s Signature Series 5W-30 Synthetic oil has a pour point of -50ºF (-58ºC) which can handle the average low winter temperature in every U.S. state, including Alaska. Try AMSOIL synthetic oil for older cars this winter to protect your older car’s engine and keep it running and starting even on the coldest winter mornings, and talk to Dave Consalvo about how AMSOIL’s products can benefit all of your vehicles.