Brent Birch, laboratory manager, Champion Laboratories, supplier of Luber-finer filters, adds, "The filter should have reserve capacity 'headroom' to run the drain intervals the engine manufacturer specifies, or drain intervals the user has oil analysis data to support."
The capacity of the OEM filter serves as a good starting point. "You always want to have at least that much because that gets you to your standard drain intervals," says Bechtum. "After that, you are looking for an extension of the capacity."
Extending drain intervals
Extended drain intervals place the greatest demands on oil filters. "Extended drain intervals require extra capacity, as well as media and pleat construction that can withstand the extra duty," says Elfers. "This usually means a higher synthetic content and measures to ensure pleat stability, such as glue beads."
But not all applications call for synthetic media. "It is not correct to categorically state only a cellulose/synthetic blend or glass-type media construction is suitable for extended drains," says Birch. "Each type of construction has pluses and minuses and filter manufacturers must balance these features."
Filters must be constructed to withstand the longer duty cycles of extended drain intervals. "There are filters that have premium materials to withstand the additional length of time in service and exposure to the elements," says Birch. "This includes elastomers, filter media, metal parts and adhesives."
On standard filters, these components often do not offer the necessary durability for extended drains. "Because it is a very cost-competitive market for standard filters, you cannot afford to put expensive parts on there," Bechtum explains. This is why Donaldson offers its Endurance line, which is specifically designed for extended drain intervals.
Donaldson also offers the Endurance Plus line for the on-highway market, and is looking to expand this product into the off-road market. "The engine oil will actually wear out before the filter in many applications," says Bechtum. These filters extend oil life by releasing additives to replenish depleted additives.
Oil filters must be tightened to the proper torque specifications. "Over-tightening can damage the can or over-compress the gasket," says Elfers. This may cause leaks and make it harder to remove the filter when needed. Always check for leaks around the filter and drain plug.
Also apply a light coat of oil to the sealing ring prior to filter installation. "Once that seal begins to make contact, you still need to turn the filter," says John Hacker, director of liquid filtration development, Donaldson.
"Applying a film of oil to the gasket reduces friction and gives you a better feel for the torque being applied," says Elfers. "It also prevents the gasket from turning and twisting in its groove."
"To put a filter on 'dry' imparts unusually high torsional loads on the elastomeric material, and greatly increases the potential for the filter to be in an under-torqued condition," Birch points out. It can then loosen and leak.
"Damage to the filter canister/shell by the installation tool is also likely when installed with a dry gasket," Birch adds. "Filters with dents and damage should be replaced immediately as the filter assembly may not resist the pressure impulse and vibration loads as designed."
Installation information is usually printed on the side of the filter can. "The side of the can will tell you how many turns once the gasket has contacted the surface," says Bechtum. This varies from engine to engine.
"Careful use of a filter wrench is acceptable to achieve the required torque/turns," adds Birch.
To pre-fill or not to pre-fill
"Pre-filling oil filters reduces the 'dry start' period required to fill the empty filter, which must occur before the lube system can achieve pressurization," says Birch. "The media is also wetted prior to being subjected to the high-velocity oil that enters a dry filter upon startup. Pre-fill is a good practice when the equipment, environment and maintenance supplies are clean."