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High-Performance Gear Oil


  • Maximizes horsepower
  • Extends gear and bearing life
  • Reduces operating temperature
  • Severe service performance
  • Lower coefficient of friction
  • Superior corrosion protection
  • Separates rapidly from water
  • Meets warranty requirements
  • Environmentally responsible
  • Formulated for limited-slip differential use


  • Recommended for use in truck and automotive front or rear differentials, manual transmissions and lower gear units of marine engines that specify use of an API GL-5 or GL-4 fluid.
  • Non-corrosive to soft yellow metals (brass, bronze, copper, etc.) and synchronizer safe.
  • Specially designed to extend gear and bearing life, Max-Gear provides superior corrosion protection over competing conventional and synthetic gear oils.
  • Engineered to provide maximum protection to heavily loaded gears while maximizing power throughout the drive train.
  • Outperforms ordinary gear oils by combining the highest quality synthetic oils with Royal Purple’s proprietary Synerlec® additive technology.
  • Makes gears run smoother, quieter, cooler and longer without overhauls.
  • A direct reduction of drag in the drive train has huge advantage for trucks and other 4-wheel drive vehicles: better gas mileage.
  • Formulated with a friction modifier additive – no additional additives are necessary.
  • Available in the following viscosities: 75W-90, 75W-140, 80W-90, 85W-140 and SAE 90