A reader asks: I own a Nissan Skyline GTR with the twin turbo RB26 engine. The previous owner used 0W-40 motor oil. I’ve read online that 0W-40 might be too thin. Is 10W-40 a better option? I will not be winter driving it at all, but might occasionally start it up during the nicer winter days to circulate the oil.

0W-40 Or 10W-40 For Nissan Engine?

AMSOIL 0W-40 Signature Series Synthetic OilOur answer: This model was never sold in North America, so it isn’t included in AMSOIL’s application guide. As this is an older car (RB26 models were made from 1989-1994), a search doesn’t seem offer much in the way of official Nissan oil suggestions. Contributors to Skyline forums use everything from 10W-30 to 10W-60.

The previous owner’s use of 0W-40 would be right in the middle of that range. AMSOIL Signature Series Synthetic 0W-40 would be a very good choice. Remember that this product is still a 40-weight oil at operating temps, so there are no grounds to call it “too thin”. It simply has a very wide operating range. Signature Series Synthetic 0W-40 also has a strong resistance to shear-down, metal-to-metal contact and volatility boil-off. It is formulated for turbo-charger service. It meets the latest Nissan GTR motor oil AMSOIL Synthetic 10W-40 Premium Protection Motor Oilspecification. Note that it is also suggested for the 707 horsepower Dodge Hellcat engine. The wear control abilities of this product are not a concern.

Another great candidate for your Skyline would be AMSOIL Synthetic Premium Protection 10W-40 Motor Oil. Premium Protection 10W-40 is an “old school” formula that is loaded with zinc and phosphorus for powerful anti-wear protection. It is also designed to withstand the extreme heat generated by turbo-chargers. Were it our Skyline, we would likely lean toward this product over any other in the AMSOIL motor oil line-up. Not because it is a 10W-40 versus a 0W-40. More so because its high-zinc formula is ideal for older engines.