In the beginning, our truck engines didn’t come with oil filters and service intervals were incredibly short. Eventually, the factory full-flow oil filters we have today came on the scene and added a layer of protection to our engines’ moving parts. These spin-on filters typically trap particles down to approximately 10 to 20 microns.
| The FS-2500 bypass filtration system was installed on our ’05 Dodge Ram with the 5.9L Cummins in only a few minutes. You can see exactly how the heavy-duty filter bracket easily bolts to the engine. The filter head then bolts to the bracket. This ¾-inch filter bolt in the center of the housing keeps the filter bowl attached. Stainless steel lines are an option we decided to go with. The oil pressure “IN” line is routed from the factory oil filter housing (first remove the plug) to the new bypass filter head.
Enthusiasts piggyback bypass oil filters on their engine’s factory oiling systems because bypass filters can screen out particles as small as 3 microns. This is important, because depending on crank angle, engine tolerances are only 2 microns, and any particle in the oil that’s larger causes wear.
The Advantages of a Bypass Oil System
Clean fluids are the cornerstone of engine longevity and sustained performance, but another benefit is increased oil change intervals. Filtration Solutions Worldwide, the maker of the FS-2500 bypass oil system, encourages diesel owners to get their oil analyzed in order to get the maximum benefit of its filter. With oil analysis, one can see the difference before and after the install of a bypass filter. Still, most non-fleet users will probably not go this far and will instead use the filter as added insurance against engine wear and in case an oil change goes longer than expected.
Clean Diesel Requires More Filtration
Today’s EGR-equipped engines benefit from the FS-2500 because it is good at removing soot. In one case study on a Metro bus, soot was reduced 60 percent with the bypass filter installed. Engines aren’t the only things that benefittransmissions need clean fluid, too. Clutches inside automatic transmissions wear and release particles just like the dust given off by your brakes. Precise valvebodies using exact tolerances work like hydraulic circuits telling the transmission how to shift. If these malfunction because of dirty fluid flowing through them, severe transmission problems develop because of the erratic instructions. Some of the most common problems we experience with our diesel engines and transmissions can be resolved with the addition of a bypass oil systemhere is how to be ahead of the curve.
| The return line goes to a new swivel cap that screws into the valve cover, but a cylinder head return is also an option. The plastic sheathing protects the stainless steel lines, which are the same thing commonly used for turbocharger applications.
Price list:
’05 to ’07 Dodge 5.9L
(underhood mount to swivel cap return) with stainless lines: $608.00
’03 to ’07 Dodge transmission kit with stainless steel lines: $608.50
Replacement element: $26.95 (quantity discounts available)
What to Look For in a Bypass Filter
Efficiency: Filtration Solutions Worldwide says to make sure your filter is as efficient as possible at removing contamination from the oil. According to third-party tests conducted by the Southwest Research Institute, the FS-2500 is more than 99.58 percent efficient on all particles from 3 to 50 microns. The results are available for everyone to see on its website.
| The FS-2500 filter element is very easy to replace and comes with an O-ring and seal that goes on the filter bolt. A bypass filter is able to be more restrictive than a spin-on full-flow filter because only a small portion of the fluid is routed to the super-fine mesh matrix. The cleaned fluid is then routed back to the pan, and eventually all the fluid gets its chance to go through the bypass filter.
Flow rate: According to Filtration Solutions Worldwide, the FS-2500’s average flow rate throughout the life of the element (10,000 miles for Class 8 trucks) is 1 gallons per minute. This is very slow relative to what your oil pump is displacing, but fast enough to keep up with contaminant creation. All the oil in your engine will move across the element in the FS-2500 eight times per hour. That flow rate, along with the efficiency on all particles 3 microns and larger, makes the FS-2500 capable of capturing all the contamination that will cause wear on moving parts within the life of the element.
Expenses and size: Some bypass filters on the market displace 1 to 5 gallons of oil every time you change the disposable element. The FS-2500 only holds 1 quarts, which means less to top off when you change its element. This small size also helps with mounting (about 11 inches tall and 5 inches wide).
Dirt-holding capacity: Given its flow rate and efficiency, the FS-2500 is able to keep up with contaminants for about 10,000 miles. You do not change the OEM filters on the engine until you change your oil, or at least once a yearwhichever comes first.
