Questions and Answers

Q. I just want to know, why? What would possibly make it justifiable to spend 3x as much on a CAT filter. Because it’s not any better of a filter than an AC Delco.

A. Well in most cases the cat filter is about the same cost as the ACDelco’s filter and depending just where you get your filters they could be less.

Q.  Waste of money.

A. Any better filtration is worth the money. If your truck is disposable, then you are probably better off with a stock filter. This is one of the problems with Social Media, someone can voice an opinion based on nothing but other social media posts and influence people. It’s a shame, that people listen to them. 

Q. How did you make the adapter?

A. Spent 2 years drawing and finding a machinist to make it. The first guy I went to wanted $900.00 for the first one, and $90.00 for any others. It wasn’t easy, every place I went wouldn’t talk to me until I found a guy working out of his garage.

Q. My concern is the lack of anti-siphon valve especially in colder weather. Have you noticed if there was difference after startup between the cat and stock filter? Is the pump having to refill the filter after every shut off?

A. No, when they added the anti-siphon valve in the 70’s like I said earlier was to correct poor manufacturing and that was before they started to manufacture the engines with CNC, I had an increase of oil pressure during cold start, but when warmed up I couldn’t even tell the difference, and once the oil gets cold the oil flow is slower, and since the filter is almost below the oil pan not above it like in the older gas engines.

Q. I’ve heard the Cat filters are more restrictive.

A. Yeah, I have heard that too much, I called my contact at Caterpillar, and the Advanced filters I’m using have design 1 PSI restriction. The older filters that Caterpillar had manufactured for them had a higher restriction. There are a couple of pictures showing the differences in the two filters.               

The outlet filter holes on both filters R) ACDelco’s L) Caterpillar. The ACDelco’s uses 8-5/16 holes and the Cat uses 10 3/8-inch holes. 

In the other pictures, you can see the difference in the center tubes and the bypass valve in the ACDelco’s filter. The ACDelco’s uses a steel center tube with smaller holes again. The Caterpillar uses a nylon center tube with large elongated holes for better flow. The Caterpillar also uses acrylic beads and spiral roving to keep the pleats in place resisting laying over with the long-pleated paper plus larger flow rates.


Since we are comparing, The CAT media is 2.11 times longer and the pleats are 1.13 deeper making the CAT filters area 2.39 larger than the ACDelco’s. That means 25/30% more area than the ACDelco’s. 

So, I went to the parts store and looked at the WIX filters for the 99 Chevy with a 5.7 and 2015 Duramax, in the picture on the next page the left filter is the gas motor on the right is the Duramax filter. The Duramax filter is smaller, the filter on the left is rated at 3000 miles between oil changes, the Duramax filter is rated at 7500 miles. You must wonder how there can be such a difference between oil change intervals? Does the Duramax run cleaner? Not with all the soot in the oil. But with a bypass valve you can extend the life of filter by letting the oil bypass the filter in the last miles of the oil change interval. 


 Q. If you want a better oil filter set up go for a bypass in my opinion.

A. That’s exactly why I started on this. I wanted the best filter I could find without going to the expense of a bypass filter. See my goal was to find a filter that did better than a stock, not too bad in the cost and I could find in town, any town. I found filters that did way better than stock and had a price tag that was way better than stock also. A bypass filter set up can cost you upwards of $350.00 and installation around $200.00, then you must buy their bypass filter element with a price tag of close to $100.00. The K-Trans F1 filter adapter and a Caterpillar filter costs around $75.00. In some cases, depending on the oil used we have gotten better results than a bypass filter.

Q. What engines does your adapter fit?

A. The adapter fits all years and all engine codes. Recently, we have come out with an adapter that is made to fit the 2001 to 2011 without removing the old filter nipple. So, on 2001-2011 with the no wrench flats you would use the K-Trans F2 adapter and on 2011-present with wrench flats you would want the original K-Trans F1 adapter.

Q. interesting have you had any problems with the adapter coming loose even once it is torqued?

A. No not at all, like I said it’s only torqued enough to keep the adapter in while you change the filter, Chevy torques the one on my truck to 20 ftlbs from the factory. However, on the LP5 engine code it seems that they have started to use some form of Loctite.

Q. What year and engine codes does your adapter fit?

A. Our K-trans F1 adapter fits 2012 to present Duramax LML & LP5 engine codes. Our F2 adapter fits 2001 to 2011 Duramax LLY, LB7, LMM, all models without wrench flats. Our G2 adapter fits all Ford 6.7 PowerStroke. As to date the only nuance is the Kodiak trucks which take a shorter filter (324-2598) due to a transmission bracket

Q. Donaldson makes Cat filters. Amsoil by micron ratings and capacity are the best on the market. Donaldson makes Amsoil filters as well, but they are made to Amsoil's specs. 

A. Ok, we have been working with Caterpillar for about a year. 

Caterpillar designs and manufactures the majority of their engine liquid filters (Lube, Fuel, FWS) through a joint venture called Advanced Filtration Systems Inc. (AFSI). This joint venture manufactures filters exclusively for Cat Equipment. For the remaining filters Caterpillar leverages other suppliers to build filters to their strict specifications. In most cases these filters are different than “will-fit” options these suppliers offers. . 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.” 

Caterpillar started to make their own filters around 1986 when they realized that a good filter was paramount to maintaining their equipment. Since they work in an environment that allowed the research into equipment failures, they were able to determine the cause of the failures and what needed to be done to remedy situation. The majority of failures where due to the inconsistency of metal end cap adhesion to the filter media. This inconsistency lead to internal leak paths that allowed dirty oil to bypass the filter media. This led to the development of molded, urethane end caps that ensure a consistent seal. Other failures were due to metal contamination in the oil due to the assembly of the filter, so they changed the steel end plate and steel center tube to remove that contamination. Those being replaced with a softer, thicker aluminum top plate, molded end caps, and a nylon center tube, cutting down on the metal shavings during assembly. Other improvements were the spiral roving and acrylic beads, but most of all an advanced filter material.


Q. How can you tell the differance between the filters that Caterpillar makes and the others?

A. You can distinguish between filters manufactured at Caterpillar and those that come from another supplier. Without cutting the filter you can see the ones made at AFSI and have an aluminum top plate, and the plastic center tube. Along with the new artwork design to make them easier to identify (see pic above). Left new Artwork, Right old artwork, check for aluminum top plate. Caterpillar conducts a great deal of testing to prove the value that our filters.

It has taken me about a year to get this information, So, if any one tells you they know everything about Caterpillar filters by looking at a website, they don’t, Caterpillar doesn’t publish any information about their filters on a website. I think that is one of the problems with social media, behind a keyboard everyone is a subject matter expert, and they can google anything and them take it in any context they want. We at Karenstransport, have been trying to look past all that and get to the people who know. Sometimes we get answers sometimes we don’t.

Q. Do you have the bypass pressure, micron rating, nominal/absolute, and the efficiency of the cat filter?

A. There is no bypass in the Cat filter, See I have a problem with the bypass valve the idea is that it opens when you start your truck, when you throttle up and the oil pressure changes, when the filter fills up. But since there is no way to tell when it opens you don’t know. There is no alarm. Plus, if you have a failure, a stock style filter will fill up with debris, then the bypass valve opens, and the debris will continue into the engine with no restriction. The micron rating starts its curve at 4 microns with just less than 20% efficiency and at 21 micron it gets 100% efficient. So, anything greater than 20 micron gets filtered out and below that it’s a curve to 4 microns. In other words, everything gets filtered. The filter is big enough for me to aim at getting 10,000 miles on an oil change.

Q. That you over paid for an oil filter

A. We have been slowly creeping towards the idea that the cheapest is the best way, we have seen to have missed somewhere that it’s not the most economic. Yes, you can but a cheap filter, and yes, every parts store is fighting to provide you with the cheapest filter. Do they care about your truck or are they just trying to sell you a filter? And as I said earlier a Caterpillar filter is only $17.45 in some cases an ACDelco’s filter costs more. 

Q. But there are million-mile Duramax powered trucks out there rocking the stock oil filter.

A. Yes there are, but I bet they are very well maintained. I’m not saying that I have the only other option, I’m just trying to get the best I can, and maybe I can help others. But if I can save a turbo, or camshaft, or oil pump. I’m thinking $ well spent. Getting 10,000 miles on an oil change isn’t a bad thing either. The other thing is a big truck is made to run 1,000,000 miles every one of them. You use the exact same oil, the only that is different is the filter.

Q. Ok, someone asked why this adapter is any better than the other things, on the market and what about bypass filters. So, let me explain. 

There is a big difference between a full flow system and a bypass filter system. Your diesel truck came from the factory with a full flow filter and it filters all the oil passed through it. With a stock filter its filtered down to 40 microns. A bypass filter is an additional filter that you add on. It filters a portion of the oil that goes through the engine and routes it back to the oil pan. This oil is filter down to 4, 8, or 10 microns depending on the filter you buy. In the bypass system its suggested that the contents of the oil pan are filtered an additional 8 times an hour. The biggest difference is the cost. A bypass system will cost you a little shy of $500.00 installed. A 1 to 2-micron full flow filter will cost you about $500.00, and you must clean it between use. 

Q. If Isuzu had wanted a different filter on their engine don’t you think they would have made it that way?

A. I don’t think Isuzu had anything to do with this filter. First, it’s a standard American thread. 13/16-16 the same thread Chevy has used for years. Isuzu is metric like M20-1.5. Secondly, none of the Isuzu trucks have a bypass valve in their filters. None. I think the Duramax filter was an off the shelf solution for Chevy, they went to something that worked for them and had Isuzu install it. 

Q. Would this work for high performance trucks?

A. This is almost mandatory for high performance trucks. When you increase the horsepower beyond the designed limits you put greater forces to bear on the pistons, rings, cylinder liners, bearings. Every oil sample I have seen on a high-performance truck has had more wear metals show up in their oil. Higher amounts of Aluminum, Iron and Chromium, from pistons, rings and Cylinder liners, using a conventional oil and filter won’t keep your engine running. You need an oil and filter that are designed for high performance diesel engines. Good filtration and high oil flow. Remember wear on your engine is a cooperation between your oil and filter. Essentially the oil prevents wear and the filter collects wear. In the gas market some race cars don’t even use filters. There is a hydraulic lock that automotive filters have that robs horsepower, with the cat filter there is what is called a 1 PSI delta through the filter, with the elongated holes in the center tube, spiral roving and the acrylic beads to keep the pleats in place you have a filter with the least hydraulic lock possible.

Q. are you making any more products?

A. Yes, we are just releasing the adapter for the Ford 6.7 Power Stroke. We also have a design for the Dodge Cummins and the GM 6.2 & 6.5, but these are both remote systems. We are working on a release of our Allison Transmission Filter adapter, we are shooting for a transmission filter you would change every 10,000 miles to keep the transmission fluid to like new qualities over the life of your Allison transmission. Just changing you filter and adding a quart of new transmission fluid with extend the life of your transmission. After that we will be looking at the Ford and Dodge transmission filters. I know the Fuel filters for the Duramax is a very worn out topic, but we are looking into a dual water separator and fuel filter with heat for the Duramax’s in the colder environments. 

Q. I drive for a trailer delivery company, if I’m away from a place where I can get a Caterpillar filter is there another filter I can get in a pinch? 

A. Yes there are. But these are called “will fit” and although they are made by some reputable companies, Caterpillar does not recommend them for their equipment. All the changes that Caterpillar has made to their filter such as; nylon center tubes, glued ends, aluminum end caps and advanced media are to protect their million-dollar equipment. If there was no reason to change the way filters were made why would they go to the expense to start making their own and change the way filters are made. 


Baldwin   B7225 

Baldwin   B76 

Baldwin   B7600 

Baldwin   B7600SS 


Baldwin   B76MPG 

Baldwin   B76SS 

Carquest   85791 

Carquest   85791XD 


Carquest   85791XE 

Caterpillar   1R0658 

Caterpillar   1R0739 

Caterpillar   1W3300 


Caterpillar   2P4004 

Caterpillar   2Y8096 

Caterpillar   3I1283 

Caterpillar   3I1384 


Caterpillar   3Y0900X

Caterpillar   5P1119 

Champ   Labs. LFP3191 

Chevrolet   12490152 


Chevrolet   6439392 

Donaldson   ELF7483 

Donaldson   ELF7739 

Donaldson   P553191 


Donaldson   P554004 

Fiat   704036791 

Fleetguard   LF3379 

Fleetguard   LF667 


Fleetguard   LF9667 

Fram   HPH49A 

Fram   PH49A 

Fram   PH8842


GMC   6439393 

Ingersoll   Rand 35310556 

Ingersoll   Rand 85401347 

Ingersoll   Rand 85401909 


Ingersoll   Rand 92658095 

John   Deere GG17031266 

Luber-Finer   LFP3191 

Luber-Finer   LFP3191SC 


Luber-Finer   LFP3191XL 

Napa   1791 

Napa   1791XD 

Napa   1791XE 


Renault   41035000133555 

Renault   5000670699 

Renault   5000670700

Renault   5000670701 


Renault   5000682146 

Renault   5010550600 

Saab   1117285 

Saab   1347726 


Saab   562810 

Volvo   466634 

Volvo   4666343 

Volvo   478736 


Volvo   4787362 

Volvo   6884417 

Volvo   V466634 

WIX   51791 


WIX   51791XD 

WIX   51791XE 

I heard Caterpillar recommends Baldwin filters?

Caterpillar replyed  "That is completely false. There are other brands we would recommend before Baldwin." 

Will that filter fit?

Yes it will. It fits just like it was made for it.

Arn't you worried about the weight?

The Oil filter mount is held on by 9 rathar sturdy bolts. I really dont think there is any thing to worry about. You could most likely hang off the mount and nothing would happen. Its really strong.

What adapter do I need.

The adapter fits all years and all engine codes for the Duramax so far. The only problem we have had is with the Kodiak Truck. It seems there is a Transmission bracket in the way of the 1R-1807. So we also have a 324-2598 which is the same filter just 2" smaller.

Do you have an adapter for the Dodge Cummins?

Yes. We have tried to come up with something but a standard configuration can not use a larger filter. We have successfully put one on a 12  Valve motor but it was in a conversion truck. A Chevy truck, it already had a relocated A/C air compressor and the turbo drain had to be relocated. But, we have got a working remote system on the drawing board. I haven't finished with its design. Its still not available yet but the prototype is done and on its way to the CNC shop.