Engine oil filters specifications, claims and facts
Paul Dilger
As we continue our series on oil filters, let's look at engine filtration needs with respect to tolerances and lubrication oil films and then compare those needs to the claims made by today's oil filtration products. We will also look at some research General Motors conducted on 22 diesel engines with respect to quality oil filtration.
Typical engine specifications show how critical it is to have an effective oil filtration system. http://www.shoclub.com/lubricationoil/lubrication-oilpart5.html Web site and shows the bearing clearances for three different engines. This is the SHO club Web site designed to help club members select the best filters for their engines in order to reduce engine wear caused by abrasive particles.
The sizes of the minimum tolerances are hard to comprehend. The smallest total tolerance for the V8 SHO engine on the chart is 0.0004 inch. This means the oil film on each side of the crankshaft and the block's main bearing is 0.0002 inch, or two ten thousandths of an inch. What then is the largest particle that we would consider safe to pass through the oil filter, measured in microns? My best guess would be about 70 percent of 0.0002 inch or 0.00014 inch. If 1 micron is equal to 0.000039 inch, then 0.00014 inch is about 3 microns. Keep this number in mind as we go through our study.
If 1 micron = 0.000039 inch, then 10 microns = 0.00039 inch (or 0.0004 inch), the same as the minimum total oil film tolerance in the V8 SHO engine main bearing. It is easy to see that when abrasive particles are the same size as the oil film, wear will occur. Most automotive engines do not meet these tight tolerances. We will normally see around 0.001-inch oil film on each side of the crankshaft or about 25 microns. You would think it would be fairly safe to look at using a 10-micron filter to achieve excellent filtration on such engines.
What happens to the life of an engine when the oil filter does not remove all the particles larger than the oil film tolerances? In an article about oil filters in January 2006 OPE, we learned that typical efficiency numbers for paper element filters are 40 percent at 10 microns, 60 percent at 20 microns, 93 percent at 30 microns, and 97 percent at 40 microns ( http://people.msoe.edu/%7Eyoderw/oilfilterstudy/oilfilters.html ). We can see from these percentages that the larger the particle, the more efficient the filter medium. For the V8 SHO, only 60 percent of the 20 micron particles are removed, while at the same time, some larger particles are still passing through that will slowly erode the bearing surfaces.
There is a new filter test, the SAE J1858, that provides particle counting and gravimetric measurement to measure both filter capacity and efficiency. The particle count test measures the number of particles of all sizes combined per fluid volume before and after the filter. The beta (B) ratio is then used by the filter manufacturers to determine a filter's efficiency. Beta calculation of filter efficiency [beta] = #of particles upstream/ = 10,000 particles/ = 10 #of particles downstream 1,000 particles Filter efficiency = (a-1) * 100/ = (10-1) * 100/ = 90% efficiency
[beta] 10 - The particle count leads to the measurement of the filter's capacity, while the gravimetric process measures the weight of the particles before and after the filter to determine the filter's efficiency. Keep in mind that when a filter manufacturer says its filter is 90 percent efficient, it could be based on either the particle weight or on the size of the particles. If the filter's efficiency is based on particle size, the manufacturer may specify, for example, that it removes 90 percent of all 20 micron-sized particles!
This gives the specifications for the Wix 51060 filters.
( http://www.wixfilters.com/filterlookup/ResultsPart.asp?PartNo=51060 ).
All the information for both filters is consistent down the chart to the anti-drain back valve. The differences in the two filters show up in the beta ratio, the burst pressure, the maximum flow rate and the nominal micron rating. Since both filters use paper media, the difference in the maximum flow rate is due to either larger pore size or greater surface area of the media.
The consumer information on the 51060 racing filter's box says: "NASCAR performance, proven improved horsepower, no dry starts, no-leak positive gasket seal, and extreme burst pressure." (I'll cover these later with respect to all filters.) Here are some more interesting points printed on the racing filter's box that the manufacturer specifically wants you to know.
* "Not intended for street use."
* "Warning: Wix racing filters are designed for racing purposes only, and if used on street-driven vehicles, pre-mature engine wear is possible."
* "New vehicle and equipment warranties are void when this product is used in competitive racing or on modified high-performance engines."
In addition, following are some of the "exclusive features" written on the racing filter box.
* "Advanced Performance Media; providing high volume, low restriction." Because Wix is using paper media, I am left to assume it is using a larger pore size or greater surface area in the media to increase the flow rate.
* "Heavy Can and Cover." This implies the metal is thicker than the standard canister. I will be measuring them later and will let you know.
* "Zinc Chromate-plated Base Plate." This is not found on inexpensive filters!
* "Fully Perforated Spiral Steel Center Tube." This is necessary for extreme automotive oil pressure.
In most cases, you won't find any detailed specifications on oil filters unless you go directly to the manufacturer. For example, an AC Delco "Duraguard PF1218" oil filter provides the following information to the consumer: 1) Offers superior engine protection; 2) Removes engine-damaging particles; 3) Provides a durable, high-quality filter. Durable? Are they talking about the media or the shell? Don't all oil filters pretty much claim the same things? How would you compare this PF1218 filter to the interchangeable Wix or Fram filters?
Some years ago, General Motors sponsored a basic research study on diesel engine wear and fuel economy with respect to oil filtration. Fodor & Ling, affiliated with the Research Institute of Automotive Industry, conducted oil filtration tests on 22 6V-53 turbocharged Detroit Diesel Allison engines.
Three technical papers (SAE 881827, SAE 881825 and SAE 95255) were written on how ultra-fine oil filtration affected an engine's performance. These papers described the results of micro-micro filtering crankcase oil to determine the affect of by-pass filtration in the 3- to 10-micron range. Five engine components were tested: rod bearings, bushings, compression rings, oil control rings and main bearings. The emphasis of the test was to control particles in the 3-to 10-micron range. The test proved that removing additional particles in the 3- to 10-micron range will have the greatest effect in reducing engine wear. Particles in this range have traditionally been ignored, but this size range is very significant as a long-term wear factor.
Some interesting findings of this research are as follows:
* Micro-micro filtering gravimetrically reduced the particulate contamination from 0.016 percent to 0.0025 percent, which reduced the number of particles by a factor of 6. It also reduced normal engine wear by a factor of 14.
* Fuel economy was increased 0.9 percent. This may not seem like much, but is a considerable amount over the life of the engine.
* Particles in the 3- to 10-micron range create a significant amount of unforeseen wear.
* Particles in the 3- to 10-micron range create friction and power loss.
* Particles in the 3- to 10-micron range increase fuel consumption.
* Particles in the 3- to 10-micron range micro-erode engine rings.
* Particles in the 3- to 10-micron range micro-erode soft seals on the crankshaft.
* Particles in the 3- to 10-micron range micro-erode rolling surfaces.
* Particles in the 3- to 10-micron range cause the engine to wear about six times faster than it would if these particles were removed.
The ultimate benefit of these tests resulted in greater diesel engine performance over an extended fife, along with lower operating costs. These tests showed the significance of reducing the proliferation of particles generated by the engine below the 10-micron range is phenomenal. Each grain of contaminant (wear debris, mineral grain, metallic oxide) produces a small but finite amount of friction, abrasive wear and catalytic oil breakdown. Because of the vast number of harmful microscopic particles, the total effect of this abundance of debris is abbreviated oil life, substantially higher engine friction, and propagation of engine wear.
You have probably noticed very large oil filters bolted on the outside of the cab on large, line-haul trucks. These large filters are by-pass filters that filter a percentage of the oil being pumped. After the oil is filtered, it is dumped directly back in the crankcase without any of it passing through the engine. The aforementioned test results can easily relate to the benefit these large engines receive from low-micron, depth-type filtration, since these large diesels average 300,000-500,000 miles between overhauls.
In conclusion, today's engine and filter manufacturers maintain levels of cleanliness to keep consumers satisfied with their products. Keep in mind that engine manufacturers such as Detroit Diesel, Cummins and Caterpillar strive for bragging rights on whose engine will last the longest. The automotive market is more into sales and parts. Therefore, if consumers want their automotive engines to last as long as possible, they need to research the highest quality replacement parts for their application.
EDITOR'S NOTE: For more comprehensive studies on OPE engine, electrical and hydraulic certification, visit Paul Dilger's Web site at www.imslo.com. These study programs develop professional mechanics.
Paul Dilger is a retired professor of agricultural engineering at Cal-Poly State University. He worked as a mechanic in the US. Army before attending college. After graduating from college, he taught mechanics for 25 years. He is currently a private consultant helping companies develop quality service training programs.
Figure 3--Specifications for the WIX 51060 oil filter
Part Number: 51060 Standard 51060 Racing
UPC Number: 765809510609 765809129269
Principal Application Chevrolet/GMC Racing Applications
Trucks (91-05), Only
Hummer (93-06)
Style: Spin-On Lube Filter Spin-On Lube Filter
Service: Lube Lube
Type: Full Flow Full Flow
Media Paper Paper
Height: 5.178 5.170
Outer Diameter To 3.660 3.600
Outer Diameter Bottom Closed Closed
Thread Size: 13/16-16 13/16-16
By-Pass Valve Setting None None
Anti-Drain Back Valve Yes Yes
Beta Ratio [beta] 2/20 = 17/41 NA
Burst Pressure-PSI 270 NA
Maximum Flow Rate 9-11 GPM 28 GPM
Nominal Micron Rating 19 NA
COPYRIGHT 2006 Bev-AL Communications, Inc.
COPYRIGHT 2006 Gale Group
With the article below in mind the best filtering filters to be found at this time are the AMSOIL EaO filters. Continuing on the path to revolutionize the filtration market, AMSOIL has introduced the new Ea Oil Filter line. Ea Oil Filters feature advanced full synthetic nanofiber technology, making them the highest efficiency filters that are available for the auto/light truck market.
Extensive testing shows that AMSOIL Ea Oil Filters achieve a near-perfect absolute efficiency rating. The exclusive new technology used in AMSOIL EaO Filters provides filtering efficiency to 98.7 percent at 15 microns. EaO Filters are the most efficient filters that are available for auto/light trucks.
