Donaldson Filtration Solutions - Effective and efficient filtration: Whereas most 4WD filter brands have been developed by automotive filter specalists, Donaldson is an industry leader in heavy-duty filtration for off-road diesel engines. Durable, rugged and built to last, Donaldson replacement filters are manufactured to the same quality standards as the original and provide premium quality, durability and the highest level of protection for your 4WD. With Donaldson's 4WD Filter Kits your engine will operate with better protecton between filter replacements and save you on costly downtime and repairs. Effective and efficient filtration is the best preventative maintenance for hard-working 4WD's. Over the past decade, numerous emissions standards and engineering achievements have come together to create advanced, clean and flexible engines. These diesel engines operate under high temperature and require an increasingly higher degree of filtration. Quality, reliable filtration is an essential component of maintaining today's sophisticated, modern diesel engines.