I just bougth 00 gp gt about a month ago and the engine oil has been full until 2day is half. Now I need 2 put oil like this friday since I dont use the car alot.... Now my question is what kind of oil does it use? on the engine oil cap it show to put 10w-30 but in my previous car I was using 10w-40. So which oil is recommended? and also which engine oil is better? Pennzoil, gtx, peek, or which one?