Every now and then, I bring this topic back up. It’s a topic that many people don’t think about when they either change their own oil or get their oil changed. They will spend good money to use the best oil, then go with a cheap oil filter. Folks don’t seem to realize that a good oil filter is as important as using good quality oil. In this article I will talk about oil filters and I will give a comparison of a quality oil filter and a cheap oil filter.
Lately I’ve began to use only OEM (Original Equipment Manufacturer) oil filters. To be OEM means that it is a part that is built by or for the original vehicle manufacturer, and would have come on the vehicle from the factory. These filters are always of good quality (what manufacturer would use crappy filters) and are designed and built to meet the specifications required for the engine. A lot of people feel the expensive aftermarket filters are better. While the media could possibly be better, I hardly see any benefit in spending $15 more, or even $5 more than a OEM filter. The aftermarket filters are built to meet a wide range of specifications since some filters can be used across manufacturers. It’s not just about the filter media either. Some OEM filters have bypass valves in case the filter gets clogged and the OEM filters have the correct release spec, the filter tolerances could be in question, as well as the flow properties. To top it off, the OEM filters, even from the dealer, are not as expensive as some might think. Where a quality aftermarket filter for a certain Dodge may be $8.97 from Wal-mart, you can go to the dealer and get a OEM filter for around $5.50.
Here’s a little description about the above mentioned bypass valves because I will be pointing it out further in the article. Every engine has an oil filter bypass valve in the oil system somewhere before the filter, or in the filter itself. This bypass, as mentioned above, is needed in case the filter becomes clogged and it can’t provide the oil volume the engine needs. While the system is in bypass the oil will not be filtered, but at least the engine is getting oil. Those engines that have a bypass before the filter as part of the engine do not require a bypass in the filter. However, many engines do not have a built-in bypass and require the filter to have one in it. Running an engine that requires a bypass valve in the filter with a filter that does not have one is very, very dangerous. If something were to happen and the filter needs to be bypassed, there is no fail safe and a few bad things can happen. Either the filter media blows a hole in it passing oil through the hole, it starts blowing oil out of the rubber gasket due to the pressure and you lose oil in a hurry, or it blows a hole in the can and you lose all of your oil. Never under any circumstances should an engine requiring a bypass in the filter be ran without one! That said, an engine with a built-in bypass can run a filter with a bypass, but the bypass in the filter may have a different release pressure than the built-in valve. This means the filter could go in to bypass before the engine manufacturer intended.
Another important piece of an oil filter is the anti-drain back valve. This is usually a rubber or silicone flap where the oil enters the filter. This is there to keep the filter from draining back in to the engine while the engine isn’t running. Drain back can happen for a number of reasons even though the filter is hanging can down (on most vehicles). Weather the valve is made of rubber or silicone, the material has to stay pliable through thousands of miles of oil flowing past it in the harsh engine environment. On cheaper filters, the valve gets hard and it doesn’t seal properly, allowing drain back of oil and a short dry-start condition every morning.
Now that we have that out of the way, on to the oil filter analysis.
The first filter in my comparison will be a OEM Chrysler oil filter (part number 05281090) taken off of my 2007 Dodge Durango 5.7L Hemi. The second filter in the comparison is a Firestone oil filter manufactured by Champion Labs (part number TF4676) that was installed at a quick-change place on a 2007 Dodge Charger 3.5L V6. Both of these engines take the exact same filter, so it makes for the perfect filter comparison.
My first impression on the Mopar was its heavy construction. The can doesn’t feel cheap. Also, to drain the filter after removal, I had to poke holes in the anti-drain back valve which meant that the valve worked, and it stood up to the harsh environment it lived its life in. I can also see the bypass valve clearly inside just under the flange. Being as the OEM filter has a bypass in it, it means these engines do not have a built-in bypass and require a filter with a bypass.
As for my initial impressions of the Firestone, it just feels cheap. The can feels like it’s paper-thin, and that’s evident by how I almost destroyed it cutting it open while the Mopar held up well during surgery. After removing the Firestone filter from the car and setting it in the drain pan to drain while I finished the oil change, all of the oil drained out. I picked it up to carry it back to the shed after the job was done and it was as light as a new filter. The anti-drain back valve was useless when it was upside down. I can also see there is no bypass valve in this one.
After cutting them open and flipping the flange out of the way, the flange on the Mopar is noticeably more beefy. Looking at the top of the filter, the bypass valve is more evident on the Mopar with the flange out of the way, while it’s obvious the Firestone does not have one. The Mopar has a metal cap on the filter media and the Firestone uses a fibrous media of some sort to cap off the actual filter media. More on that later.
The anti-drain back on the Mopar seals around the neck of the filter and actually “clicks” when you take it off and put it on showing it seals well. It was also still very pliable even though it’s made of rubber rather than silicone. While I would prefer it to be silicone because they hold up better than rubber and stay pliable longer, the Mopar filter rubber valve seems to be made of a rubber that can handle the environment it is used in. The Firestone bypass valve just sits in the middle of the media with no seal around it, so oil could just leak past the valve without any resistance. This means oil could enter the filter, leak past the valve, and go back in to the engine without ever being filtered. When the engine isn’t running, it could just drain right back out because of this cheap anti-drain back that simply doesn’t work.
Both of the filters have a formed piece of sheet metal on the bottom of the can to keep the filter off of the bottom. What I found interesting is the Firestone uses that sheet metal piece as part of its end cap, sealing the dirty side of the filter from the clean side. This is flimsy and just like the anti-drain back valve, this could leak allowing dirty oil back in to the engine. I was rather perplexed by how cheap and flimsy this setup is.
The media element of the Mopar is built extremely well. There are steel end caps and the media is sealed to the end caps with a very strong sealant. This seal is probably stronger than the media itself. The pleats are fairly evenly spaced, and the seam is sealed with a steel clip where the two ends meet. The media itself is a synthetic media and has a thick, strong feel to it.
On the other hand, the Firestone element is as cheap as it gets. The end caps are some kind of fiber media and the element is cheaply glued to it. In fact, I found parts of the end cap that pulled away from the element with no effort, like it either wasn’t even glued or the glue let go some time during its service. Here again, this is a spot where dirty oil could leak past the filter and back into the engine. The two ends of the media are glued together with the same glue as the end caps. The media is a thin paper element with uneven pleats throughout.
Lastly, here is a picture of the Mopar bypass valve. Not only did this turn out to be a really awesome pic (click to zoom), but it shows clearly the valve and gives an idea of the build quality of the unit.
Why do oil change places use cheap filters? It all comes down to money. They could really care less about your car. This is how they give you the $19.99 oil change. These filters likely cost them about $1 each or less, and the oil costs them about $8 because they use cheap oil and buy it in bulk. They also still have to pay the employees, heat and light the place, etc. They have to make money somewhere while keeping the cost low for the consumer. People want cheap oil changes, well this is what they get, and their cars suffer. They also make more money by continuing to push the 3000 mile oil changes, but that’s another topic. I changed the oil in the Charger that had this Firestone filter with 6 quarts of Mobil Super 5000 plus a make-up quart (so 7 quarts total) and a Mopar filter (Wal-mart sells them now) for $26.65. That’s very good quality non-synthetic oil and a OEM filter for $6.66 more than an oil change shop. If you feel you MUST use an oil change shop, go buy an oil filter for your car from your local dealer, or buy a high quality oil filter from Wal-mart, take it to the oil change shop and hand it to them to install rather than theirs.
For those that already change their own oil, let this be a lesson for you. Don’t go and try to save a few bucks on an oil change by purchasing cheap oil filters. A few dollars saved now could cost you thousands later in the engine’s life.
Here is a list of some OEM filter names:
Ford = Motorcraft
Dodge/Chrysler = Mopar
GM = AC Delco. Be very careful here because AC Delco sells filters at the local parts stores and Wal-mart. Those ARE NOT the same as the AC Delco filters sold at your dealer. I have taken these filters apart in the past and the construction is the same as the Firestone filter above.
Lexus/Toyota = Toyota
VW = VW/Audi (manufactured my MANN, so you can buy MANN if you would like)
Hyundai = Hyundai (Hyundai Mobis). Hyundai specifically states in their owner’s manual, and has a TSB out that states to ONLY use Hyundai filters. They can void your warranty for this if it comes down to an engine failure that they can deem was caused by the oil filter (not that hard to prove any issue was caused by the filter even if it wasn’t).
Honda = Honda
If you feel you MUST buy an aftermarket filter, go with Wix, NAPA Gold, Fram Extended Guard (NO other Fram is good, they use paper end caps or put useless crap in the filter), Purolator Pure One, Mobil 1, or K&N. I’m sure there are a few others I missed, but those are the most readily available, so don’t send me comments saying “you missed THIS filter, you suck!” because I will delete your comment no questions asked.
I hope this helps you arm yourself with more information when it comes to maintaining your car. Treat your engine right, and it will reward you with years of reliable service.