Bypass Filter

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Guard Against Sludge: Keep Your Engine’s Oil Pristine!

Bypass oil filter system

Bypass oil systems

How an engine oil bypass filter element system works

A bypass filter element is an engine oil filter system functioning as a secondary filtration to eliminate soot and small particle contaminants from motor oil. AMSOIL EaBP filters offer high holding capacities with a service life of one to two years up to 120,000 miles, continuously removing soot and other particles too small for the full-flow filter. Constantly cleaning engine oil with the AMSOIL bypass engine oil filter system means engine oil can remain in like new condition longer, returning analytically pure oil to the engine.

Engine oil bypass filters removes even the smallest contaminants

It’s proven time and time again that engines wear faster when the oil is dirty. Even oil that has been recently changed can have contaminants suspended in it, wearing on bearings and cylinder walls. It reduces your engine’s lifespan and requires serious repairs sooner than it should. Your engine oil sump filter and AMSOIL engine oil bypass filter drastically improves the condition of your engine oil by removing contaminants like carbon, soot, and sludge to keep your truck engine, semi truck or equipment operating more efficiently and cleaner, not to mention more reliably.

For engine oil bypass filter systems, AMSOIL has the best options available to keep your oil working at its full capacity. With four options to cover almost any application, the leader in synthetics is also the leader in oil filters of all kinds.

Benefits of using a, engine oil bypass filter sytem

AMSOIL’s engine oil bypass filter elements offer significant improvement compared to full-flow filters alone. Engine oil that’s been filtered by a bypass oil filter system keeps oil analytically clean, and keeping diesel engines free of the sludge and carbon buildup.

  • A clean bypass oil filter element cycles through the oil sump capacity every hour.
  • Diesel engines are protected from soot buildup that etches into cylinders and pistons.
  • Working alongside full-flow oil filter, AMSOIL engine oil bypass filters clean oil far better than the full-flow filter alone.
  • Oil consumption is reduced since clean oil provides a better seal for piston rings against cylinder walls better.

Save more with an AMSOIL commercial account

By creating a commercial account, you save money on engine oil bypass filter elements and AMSOIL synthetic oils and fluids. With applications for all industries, including farming, industrial, construction, trucking, or others, you’ll have access to premium oil, oil filtration, lubrication, and related products at a preferred rate with a commercial account.

Efficient 98.7 percent at two microns
Equipment constantly runs on clean oil
Increased engine efficiency
Significantly extend engine life
Increased filtration capacity and life
Improved oil cooling
Increased fluid system capacity
Extended drain intervals

EaBP elements service life chart

Ea® stock code >> EaBP90 EaBP100 EaBP110 EaBP120
Service Time (Year) 2 years 2 years 2 years 1 year
Service Time (Hours) 600 800 1200 1800











Element Dimensions
Height 5.78″ 7.25″ 10.35″ 12.1″
Diameter 4.25″ 4.25″ 4.25″ 5.35″

How to tell when it’s time to change the engine oil bypass filter element

Regular oil analysis can indicate how effective the engine oil itself is, but how can you tell when a bypass filter element needs to be changed? When the filter is hot to the touch, it’s an indicator that oil is still flowing freely through the bypass system and the filter is still performing its duties efficiently. If the bypass filters are cold, the hot engine oil is no longer circulating through and it’s time to change the bypass filter.

Of course, the best option is an AMSOIL Ea Bypass Oil Filter, and one of the four options will fit your application perfectly.

Why choose the AMSOIL® brand

Engineered for outstanding oil filtration efficiency

Higher Efficiency

AMSOIL Bypass Filters have an absolute efficiency of 98.7 percent at two microns. This highly efficient filter provides exceptional filtration performance, removing all the particles known to reduce engine life.

Superior Construction

AMSOIL Bypass Filters have a marine powder-coated exterior and an anti-corrosion coated base plate to provide excellent corrosion protection. AMSOIL Bypass Filters feature a nitrile HNBR gasket, an orange silicone anti-drain valve and proprietary high-efficiency media

Soot Removal

AMSOIL has designed a high-efficiency bypass filter element that is also a soot removal device. AMSOIL Bypass Filters use proprietary high-efficiency media. This media removes soot particles two microns and larger, eliminating abrasive wear from soot agglomeration.

Increased Oil Capacity

The increased fluid system capacity and filtration life provides improved oil cooling and ensures that equipment constantly runs on highly filtered oil. Engine efficiency is increased, providing extended engine life.

Oil sump capacity chart for filter application

Pleasure vehicles, 1/2 – 1 ton trucks and small commercial engines.


AMSOIL Kit Number
Single Remote Kits BP Filter Size Engine Oil Capacity Additional Oil for System
BMK21, BMK31, BMK32, BMK33, BMK34 BP90 up to 15 qt./ 3.75 gal. 1.0 qt. w/ BP90
BP100 up to 18 qt./ 4.5 gal. 1.5 qt. w/ BP100
Dual Remote Kits
BMK23, BMK26, BMK27, BMK28 BP110 up to 24 qt./ 6.0 gal. 2.0 qt. w/ BP110

Large trucks, construction, farm and industrial equipment

AMSOIL Kit Number
Dual-GUARD® Heavy-Duty BP Filter Size Engine Oil Capacity Additional Oil for System
BMK22 (only) requires two BP filters* BP90* up to 7.5 gal. 2.0 qt. with ea. BP90
BP100* up to 9 gal. 3.0 qt. with ea. BP100
BP110* up to 12 gal. 4.0 qt. with ea. BP100
Single Heavy-Duty Kits
BMK30 (only) BP120 9 – 15 gal. for each BMK30 System installed 4.0 qt. with BP120

The primary benefits of an AMSOIL Bypass Filter System is to reduce mechanical wear, remove soot, control cylinder deposits and reduce lubricant replacement cost. Adding a bypass oil filter is a simple and most effective solution to keep any brand of engine oil clean. Clean oil can not only remain in service longer but also helps maintain engine efficiency and performance.

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