Frantz Filter

I bought a "new, old stock" Frantz bypass oil filter the other day (meaning it's old, but was never used). It's basically a canister that gets part of your oil pumped through a toilet paper roll. It's not the soft fluffy kind of toilet paper, but the thin, tightly wound, commercial toilet paper. The fluffy stuff would leave bits of that fluff in your oil, but the commercial kind is just paper.  I still have to find a place to install it on the truck, but I did get a couple of test kits from Blackstone Labs, so I need to hurry up. I'll send in samples before and after the install, and see what they show, and post the results here.

The theory is that a normal "full flow" oil filter only filters down to something like 20 microns. That's what the engine manufacturers say is a safe level. But that still means that you can have pieces of metal or whatever that are that big wearing away at your bearings. The problem is that ALL of your oil has to go through the filter; that's why it's called "full flow". In order to get enough oil everywhere it needs to be, the filter can't stop much smaller than that or the oil wouldn't travel through fast enough. That's where the bypass oil filters come in. It takes a small percentage of your oil and sends it through a much better filter. That small amount can get slowed down without starving your engine of oil, and over time, all of your oil will go through this filter and get better cleaning. Just about everyone will tell you that you should have a bypass filter. Every bit of contaminant you can keep out of your oil will make your engine last that much longer. The controversy comes from using a toilet paper roll as the filter. According to the manufacturer, almost all filters are made of cellulose of one kind or another, so just because his filter is made of paper doesn't make it more likely to fall apart than any other. In addition, most filters are relatively thin, whereas a toilet paper roll is almost 4 1/2 inches tall (the oil is pumped top to bottom). If you leave aside the argument that it might fall apart, then the Frantz filter is probably better than almost every other filter out there. Amsoil is a high-end oil company making a similar filter. The unit costs about the same, but the filters are 40 dollars each, so it will cost quite a bit more in the long run. The only other argument comes up when people claim that you won't ever have to change your oil. They say that the additives that are in oil will wear out, and you have to change your oil whether it's clean or not. Whereas the other side argue that the additives DON'T get used up, so you shouldn't ever have to change it if your car is in good repair and your oil is kept clean. It might not matter for oil in diesel engines, though. The reason your oil has two viscosity numbers (the 10 and 30 in 10w/30) is because of special molecules called "viscosity improvers". At colder temperatures, they are curled up, and your oil has a natural viscosity. At higher temperatures, they uncurl and make your oil thicker, canceling out the thinning caused by heat. But I've read that the gears, and especially injectors, in a diesel engine cut those molecules up like scissors. Commercial grade diesel oil is supposed to be formulated to prevent it, and oil with certain viscosity values have less improvers which helps as well. But I don't know if it can be eliminated entirely.

I'll take a sample of the oil before I install the toilet paper, and then a sample after I've installed it and the engine is back up to temperature. Blackstone will tell me whether the additive package is intact, and whether there are any "insolubles" (of which toilet paper would be one) in the oil. Basically, they can tell me whether the oil is good enough to be left in the engine or not. The best case scenario is that both samples will have an intact additive package, the first sample will be high enough in insolubles that they recommend the oil being changed immediately, and that the second sample has no insolubles and is fine. This would tell me that the additive packages isn't wearing out under normal use, and that the filter is doing a good job. Unfortunately, I actually expect that both samples will come back as being recommended to change, because it's been too long already. I've got symptoms of "sticktion", which is when an injector wants to stick instead of working properly. This is supposedly caused mostly by bad oil, and causes misfires and bad gas mileage. I need to change the oil, but I want to use what I've got to test the filter. Regardless, I'll be retesting at each interval, even if I have to start with fresh oil after the first test, and we'll see how long the oil lasts.