Always use the manufacturer's recommended viscosity, even at higher mileage. NEVER increase the viscosity. See the article below on why. However, you might want to try a 5W-30 high mileage oil like Valvoline MaxLife. It has extra anti wear additives and seal conditioners.

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For a 2006 NISSAN/DATSUN FRONTIER 2.5L 4-cyl Engine Code QR25DE You Would Need:

6 Quarts of SAE 5W-30 Signature Series 100% Synthetic Motor Oil (ASLQT)

1 Absolute Efficiency Oil Filter (EA15K12)

For a 2006 NISSAN/DATSUN FRONTIER 4.0L 6-cyl Engine Code VQ40DE You Would Need:

6 Quarts of SAE 5W-30 Signature Series 100% Synthetic Motor Oil (ASLQT)

1 Absolute Efficiency Oil Filter (EA15K13)

I never ask what oil they put in my honda but it has 450.000 km on the clock . Difference is viscosity of the oil . One is thick and used in the summer if where you live gets very hot and the other oil is not thick if you live in a cold climate so car will start easier and run easier in cold weather ..... so any will do until next oil change ,you will not have any problem no matter what you put .

The only other weight you could safely use on that would be 10w30. Not saying to use it but at your mileage you could use it for its viscosity.

I have a 2006 Nissan frontier it has little over 150 thousand miles I just got this car not to long ago thats why I'm confused. I bought the 5w-30 should i put this one or what should I put???