RepairPal Certified shops can diagnose and repair your 2001 Nissan Maxima. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
If your car dosn't burn or leak oil, I would use Mobile 1 synthetic or a good cheaper alternative is Valvoline, Remember use a quality oil filter also ( Napa, Wix, Hastings etc )