Short answer
A bypass oil filter takes a small stream of oil, AMSOIL says about 10 percent of the oil pump’s output, through a fine filter and returns it to the oil pan, while the engine’s full-flow filter keeps protecting the bearings. It adds to the full-flow filter; it does not replace it. AMSOIL sells kits for Ford, GM and Cummins diesels and universal kits for other engines.
Full-flow and bypass oil filters do different jobs
The full-flow filter sits in the main oil circuit, so every drop of oil going to the bearings passes through it. It has to let oil through quickly, including when the oil is cold and thick, so its media is sized for flow.
A bypass filter is plumbed in parallel. A restricted line carries a small portion of the oil, which AMSOIL puts at about 10 percent of the oil pump’s capacity at any one time, through finer media, and the oil drains back to the pan. Because it sees only part of the flow, it can use media that would starve the engine if it were in the main circuit. The engine still needs its full-flow filter.
Which bypass kit fits your engine
Single-remote kits mount one bypass filter away from the engine. Dual-remote kits move the full-flow filter to a remote mount beside the bypass filter; AMSOIL’s application dual-remote kits use an EaO26 full-flow filter and a bypass filter, both included with the initial purchase.
Check the model years and notes on each kit. AMSOIL says the Ford 6.0/6.4L single-remote kit does not fit E-Series vans or larger trucks and buses. The Cummins kit does not include an oil filter adapter: it replaces one of two plugs on top of the full-flow filter housing, and if neither plug is accessible you need the optional BK1104 adapter.
| Engine | Single-remote kit | Dual-remote kit (filters included) |
|---|---|---|
| Ford 6.0L and 6.4L Power Stroke, 2004–2010 | BMK31 | — |
| Ford 6.7L Power Stroke, 2011 and newer | BMK33 | BMK28 |
| Ford 7.3L Power Stroke | — | BMK26 |
| GM 6.6L Duramax | BMK32 (2001–2016) | BMK27 (2001–2019) |
| Cummins 5.0L, 5.9L and 6.7L, 2004–2024 | BMK34 | — |
| Other engines | BMK21 (universal) | BMK23 (universal; filters and adapter sold separately) |
Source: AMSOIL Ford 6.7L Dual-Remote Bypass System.
Source: AMSOIL Ford 6.0/6.4L Single-Remote Bypass System.
Source: AMSOIL Cummins 5.0/5.9/6.7L Single-Remote Bypass System.
Universal and DUAL-GARD kits
For engines without an application kit, such as older pickups, fleet trucks and stationary or off-road engines, AMSOIL lists universal systems. The Universal Single-Remote (BMK21) connects through a pressurized oil port. The Universal Dual-Remote (BMK23) includes the mount, mounting hardware, hose and fittings; the spin-on adapter, EaO26 full-flow filter and bypass filter are sold separately, and the adapter must match your engine’s filter thread.
The DUAL-GARD system (BMK22) also connects through a pressurized oil port and includes the mount, mounting hardware, hose and fittings, with the bypass filter sold separately. AMSOIL notes that the EaBP120 filter does not fit the DUAL-GARD or the Universal Dual-Remote. The bypass replacement-parts category carries the fittings, hoses, adapters and gaskets used in these systems.
Source: AMSOIL Universal Dual-Remote Bypass System.
Source: AMSOIL DUAL-GARD Bypass System.
Planning the installation
An installation needs an oil pressure source, a mounting location with clearance for filter changes, hose routing away from heat and moving parts, and a return path to the oil pan. Follow AMSOIL’s installation and servicing instructions for the exact kit.
A remote filter and hoses hold extra oil, so the fill quantity at each change increases. Check the dipstick after the first run. If you are not comfortable tapping a return or routing pressure hoses, have a qualified shop do the installation.
EaBP filter service limits
AMSOIL’s EaBP bypass filters come in several sizes, and each has a maximum service life by miles, hours and time. Do not exceed the first limit reached. Replace the full-flow filter on its own schedule, and use the bypass filter part number listed for your system; Donaldson and WIX bypass filters are also sold through AMSOIL.
Any decision to change the oil drain interval belongs to the engine maker’s requirements and, where you want to go further, to used-oil analysis. A bypass filter does not by itself establish a longer interval.
| Filter | Miles | Hours | Time |
|---|---|---|---|
| EaBP90 | 60,000 | 600 | 2 years |
| EaBP100 | 70,000 | 800 | 2 years |
| EaBP110 | 80,000 | 1,200 | 2 years |
Source: AMSOIL Ea Bypass Oil Filter.
Sources checked . Prices and product guidance may change.
Frequently asked questions
Does a bypass oil filter replace the regular oil filter?
No. It works alongside the full-flow filter, which still protects the engine’s main oil circuit.
How often do I change an EaBP100 bypass filter?
AMSOIL lists 70,000 miles, 800 hours or two years for the EaBP100, whichever comes first. The EaBP90 and EaBP110 have their own limits in the table above.
Will a bypass filter let me skip oil changes?
Not by itself. Follow the engine maker’s requirements, and use used-oil analysis before changing an interval.
Which kit fits my truck?
Start with the engine table above, then confirm the model years and notes on the AMSOIL page for that kit. For engines without an application kit, compare the universal systems.
General maintenance information. Always follow your vehicle or equipment manufacturer’s requirements and the current product data. Questions? Email [email protected].
