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Why certain oils are noisy

Unprecedented noise occurs when a product with 100% PAO base is used.
I wonder if it’s my car’s problem or if certain oils can be noisy.

Make model year miles?

The recommended oil for the engine is described in the owners manual. There is a viscosity grade, 5W20 for example, and also API (American Petroleum Institute) description that uses letters and numbers, and maybe some more information.

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PAO base stock is used in real, full synthetic motor oils. To that end, they don’t need to warm up as much to get to the rated running viscosity. (Oils are rated at 100 C (212F) and 40 C (104F) for the summer and winter rates) The oil starts thinner and stays thinner. The curve is flatter than cheap synthetics or conventional motor oils.

Being thinner at cold startup may cause more noise in some engines but that should go away once at operating temperatures.

Don’t be absolutely sure it is the oil. I assume you change the oil filter also. My son bought a new 2007 Hyundai Sonata, no problems with it and when he bought a 2015 he sold the 2007 to his daughter. Both cars had a 2.4 four cylinder engine.

the 2015 had some free oil changes from the dealer at 6 month intervals but the first time he changed the oil himself the car sounded like a threshing machine. He called me and I could hear the racket over the phone. I advised him to call the dealer, about 30 miles away and see what they had to say.

They told him they had a lot of similar complaints and had concluded that these cars did not like aftermarket oil filters.

THey also said that his warranty was good no matter what brand filter he used but their experience was that the Hyundai filter would make the noise go away. He changed to the factory filter, the noise went away and he found out the factory filters were no more expensive than aftermarket.

I had sort of the opposite experience. I had a 2002 Town and Country 3.3 V6 with about 60,000 miles and I started getting lifter noise on overnight startup. I had been using Fram filters so I put in a Mopar. No difference. I read on a Chrysler minivan forum to try a Motorcraft filter if you had this problem.

I did, and no more lifter noise.