The Rest of the story


When I bought my 2015 Chevy truck I really wanted it to last 1 million miles. My first mentor always said that with clean oil, clean fuel, and clean air a diesel would last for almost ever. With so many discussions about filters what to use and what not to use the conversation is very confusing. Some people like this brand and rightfully so they have been using them all their life, their father used them, and their brother used them. Some people are marketing magnets so influenced by new and amazing products. That is not what I wanted. I wanted something that was solid, tried and true. I wanted something that would be here tomorrow, and most of all it had to be easy to install and fit into the stock housing. I researched it until I came down to 2 filters. I really didn’t like the options at all. I couldn’t go to any parts store in town and get a filter if I need one right now. I didn’t like the idea of having hoses and mounts that required drilling holes into the frame. Most of all it had to do a better job than the stock filter.

So how do we pick the right filter?

I started using my experiences with the U.S. Navy, and years of education on Diesel and Gas turbine engines, plus my time with the big truck industry. Today’s trucks are made to run millions of miles. It would only go to say that they should have better filters, and of them I found Caterpillar to be the best. I had tried most of the other filters I could get my hands on Donaldson, K&N, Amsoil, Baldwin, and Fleetguard. All of those were about equal in performance. The one that stood out was Caterpillar. Remember Caterpillar has been around since 1926. There are a lot of ground moving equipment manufacturers out there but really, when you turn your head and look a piece of equipment and it says Cat and it’s still running they have to be doing something right. It means something built right, and maintained. Yes they are expensive to repair, "but it’s kind of like a divorce attorney, they’re expensive because they’re worth it."

Now the search begins and I had four things to research; Filtration, Construction, Flow, Cost. I wanted facts not opinions, so that meant staying away from the many forums, Facebook, and such. 

  1. Filtration

A lot of thought about filtration, but it boils down to three things; the media, the size, and the efficiency.

“Approximately 75% of the contaminants trapped by the oil filter are combustion byproducts (soot and sludge) rather than engine wear particles or dust or dirt from the outside environment.

The filter’s holding capacity (how much dirt it can hold) as well as its efficiency are important because both determine how long the filter can last before it has to be changed. You want a filter with high efficiency (98% or higher) to trap as many contaminants as possible, but you also want a filter that has adequate capacity so it doesn’t plug up before it is changed. If the filter media becomes clogged to the point where the filter goes into bypass mode, the engine will be running on unfiltered oil.” Diesel Engine Oil & Filters - Larry Carley.

“While the benefits of clean oil are significant, historically low-quality filters are frequently specified for automobile engines. Consider this, according to a study by one engine builder, particles smaller than 10 microns generated about 3.6 times more wear (rods, rings and main bearings) than particles greater than 20 microns. Typical automotive oil filters remove particles 40 microns and larger.


AC Delco Division of General Motors tested diesel engines and found an eight-fold improvement in wear rates and engine life with lower lube oil contaminant levels. In a related study on both diesel and automotive engines, General Motors reported that “compared to a 40-micron filter, engine wear was reduced by 50 percent with 30-micron filtration. Likewise, wear was reduced by 70 percent with 15-micron filtration”. Read that again. That's a lot of motivation for clean oil!” 

Oil filter design is somewhat of a balancing act between particulate size, filter medium, surface area of filter medium and oil pressure. The finer the filter medium, the shorter a filter’s lifespan before it begins to show pressure drop and the oil filter bypass valve is opened. However, new synthetic filter media and pleating configurations have managed to overcome some of these drawbacks. We have the capacity to filter out particles smaller than needed (less than two microns) to protect the oil between bearing surfaces, but determining the right balance can be a real puzzle.

Oil Filter Selection 101

For the same reasons it is important to customize the selection of Motor oils, there are several similar options and considerations that must be navigated when selecting an engine oil filter. In fact, there are so many issues involved in automobile filtration that a small book could be written on that subject alone. Maybe we'll write that book someday, but for now this article will present just the essential factors for oil filter selection - summarized in the list below:

1. Size and Capture Efficiency

2. Dirt-Holding Capacity

3. Pressure-Flow

4. Design and Fabrication Integrity

Now getting started, look I had to look at all the cut-away filters on the internet, some have paper tube construction, metal end caps, and stamped steel end plates. I have seen the inside of machine shops where parts have been stamped; machines looked like a magnet with shavings all over from the stampings. Have you ever tried to get a filter off and the case twisted and you had to poke a screwdriver through it to get it off? I really didn’t want all that grief. So, I needed to start looking at the options from a different market. The commercial truck market so much ahead of the Auto/Truck market when it comes to filters. Commercial filters are constructed way better than Auto filters. I have still seen a mechanic drive a screwdriver through and remove a few of them, I wasn’t sure that it was the filters fault or if someone had overtightened or if the filter had been on so long that it was adhered to the housing, again I didn’t need all that grief. I have seen people testing with baby powder, and anything else to try to come up with some measure of efficiency. I mean really how many times have found baby powder in your oil? Manufacturers are even getting away from the Micron rating because it can easily be manipulated. How many sales departments have rounded up a number just because it looked better on sales? 

1. Size and Capture Efficiency

2. Dirt-Holding Capacity

Now I had to look at size the relationship between filtration and size, this  can’t be ignored. If you have high filtration and nowhere to put it you’re not any better off. The filter will fill up sooner, fill the media and stop filtration. I have been told many times that it’s not the size of the filter but the number of pleats inside, and if you stuff too many pleats inside the oil will collapse the filter media and again you’re no better off. By the way I have not ever seen a filter get so full that it clogs the oil passage, usually they end up tearing and become useless. So a bigger filter was required. A Caterpillar filter has twice the filtration and 3 times the media, and the case is twice as big.

3. Pressure-Flow

I have heard of trucks with low oil pressure, I even refunded an adapter because it changed the oil pressure to 60 psi. It was claimed that that year of truck was designed to run with 20 Psi oil pressure. Some have called the dealer and they said so. Well I disagree, first of all if you’re getting your information from a Forum it’s all based on Opinion. If you’re calling a dealer for your information then most likely they just want to get you off the phone. You’re wasting their time because you’re not paying. Rarely do they give out anything for free. The Flow on the filter can be measured by watching your pressure gauge. After I installed the Cat filter on my truck I immanently noticed the oil pressure increase to 70 Psi and then as the engine warmed up and the oil thinned the pressure was back to normal. The restriction that was the oil filter, and now it was gone.

3. Design and Fabrication Integrity

I have actually stood by A/C Delco before I started this but have firmly stood by Caterpillar since then. Everything about the Caterpillar filter is better, especially their construction.

Acrylic Beads  

Cat Filters: 

Feature acrylic beads to maintain even pleat spacing and prevent bunching.

Eliminate bunching to help capture and hold contaminants until the next change interval. 

Help to maximize the surface area throughout the life of the filter. 

Other brands: 

Commonly experience pleat bunching, which leads to clogging and shorter change intervals. 

Have bunching that can trigger bypass which allows contaminants to circulate through the system and cause additional wear. 

Spiral Roving 

Cat Filters: 

Feature fiberglass spiral roving that keep media pleats from flexing as fluid travels through the media.

Eliminate pleat movement, ensuring that contaminants are captured and held away from the clean side of the media. 

Other brands: 

Have pleats that often flex and release contaminants through the filter media into the clean side, resulting in additional component wear 

Non-Metallic Center Tubes 

Cat Filters: 

Use fiberglass-reinforced nylon for center tubes to eliminate a common source of metal contamination. 

Are 30% stronger than typical metal tubes to help prevent collapse during pressure spikes and machine cold starts 

Other brands: 

Use metal center tubes which can carry metal contaminants left over from the manufacturing process 

Allow contaminants to be picked up by the fluid from the clean side and continue through to cause component wear 

Molded End Caps 

Cat Filters: 

Feature molded end caps that eliminate the possibility of gaps 

Have a filter media that’s inserted into polyurethane during the manufacturing process before it hardens to create a bond that keeps contaminants confined to the dirty side of the filter 

Have an aluminum base plate that joins to the molded end cap and is enclosed within the one-piece canister, resulting in greater burst strength and the elimination of a potential source of metal contamination.

Other brands: 

Feature metal end caps that are glued on top of filter pleats 

Have end caps that gap and allow contaminants to reenter the clean side of the fiber 

The advanced design features of Cat Filters create and maintain high standards for each and every one that you use in your engine, hydraulic system and transmission. You can rest easy knowing that your Cat Filter will deliver consistent quality and protection, from when you first install it, until the next change interval.

Then there is the bypass valve,

Most oil filters with internal bypass valves will crack in the range of 10 to12 psid (pressure differential in pounds per square inch). A new oil filter at engine idle speed may have only 1 psid of pressure drop (often much less). As dirt accumulates, the pressure rises and all the oil will be passing through the filter media until the bypass cracking pressure has been breached. As previously noted, the pressure differential is also proportionally affected by flow rate (engine speed) and viscosity. In addition, the filter flow restriction has an impact on fuel economy – it takes energy and power from the engine to push oil through an overly restricted oil filter.

Additional Information


I constantly get from some conversations with people, “Just get a Donaldson they make Caterpillar filters” since I tried Donaldson I was not convinced. I got an account with Caterpillar and once I discussed what I was doing with the Parts manager he directed me to the Head of Marketing with AFSI who actually make Caterpillar filters.  I asked him that very question and this was his response.

“As for the comment about Donaldson, we get that all the time. While Advanced Filtration Systems Inc (AFSI) is a 50/50 joint venture between Cat and Donaldson they only produce Cat filters; there is no Donaldson product that comes off that line. AFSI's main focus is on engine liquid filtration (Lube, Fuel, FWS) which accounts for about 80% of the filters we sell. Obviously AFSI does not make all of our filters but when we use other suppliers the filters are built to our specifications and requirements. In many situations the filters that are produced by these other suppliers are different than their will fit option. In some cases we have even gone to the extreme of purchasing and installing Cat-specific tooling in these other suppliers' factories so that our filters are differentiated.”

Extended Drain intervals 

This I think is where this filter really shines. In a 2008 report form California Integrated Waste Management Board they discuss high filtration and extended intervals.

“HE Oil Filter Project Conclusions The California Integrated Waste Management Board (CIWMB) contracted with the Department of Toxic Substances Control (DTSC) to study high efficiency (HE) oil filters on State vehicles.

The project was designed to: 

1. Discover why State agencies had not yet adopted this technology. 

2. Identify barriers to its adoption. 

3. Determine how the barriers could be overcome. 

4. Demonstrate the technology’s performance in actual fleet operations. 

HE filters were demonstrated on 119 vehicles including large diesel trucks and buses, medium size gasoline trucks, passenger cars, and compressed natural gas buses. The vehicles accumulated 2,844,172 miles, and 540 oil samples were collected and analyzed. No engine failures were reported during the study. DTSC found that it is possible to achieve longer oil change intervals without observable impacts on engine life. Follow manufacturers’ recommendations for oil change intervals and institute routine oil analysis programs to extend oil change intervals Staff used existing oil change intervals to establish a baseline for comparison. Staff then used oil analysis results to propose new oil drain intervals. DTSC found that for most fleets, oil drain intervals can be extended beyond their current level to the maximum level recommended by the vehicle manufacturer- and beyond. The fleet manager survey confirmed that today’s average oil change interval is considerably shorter than the maximum suggested by oil condition-based analysis results. The fleet managers’ survey showed an average passenger vehicle oil change interval of 4,460 miles, well below some manufacturers’ recommended 7,500 or even 10,000 miles. The oil analyses showed that oil drain intervals can be extended for all vehicle types studied. Oil sampling results indicate that in many cases, oil drain intervals can be extended beyond the maximum level recommended by the vehicle manufacturer. For fleets that have already extended their oil drain intervals to the maximum recommended by the manufacturer, many can further extend oil change intervals by using better oil and by establishing oil analysis programs to determine the optimum drain interval. Routine oil analysis is an important tool that ensures good oil condition and provides safety for the engine. In some cases, oil sampling alone can be used to extend drain intervals. A basic oil analysis program including physical and chemical parameters, like viscosity, TBN, oxidation, nitration, and common oil contaminants, like water, dirt, and wear metals, would be sufficient to ensure oil condition and satisfy fleet managers.”


So we here at are doing just that we are doing the due diligence, we have started a sample program and will post the results. Our goal is to find out when the Caterpillar filter start to go out. One of our first samples is back and a truck with 50,000 miles on it and 7500 miles on the oil and filter. You be the judge.