I finally had a few moments of “free” time to cut open a used Amsoil SDF-42 oil filter (from my wife’s 850 Volvo) and inspect it, plus measure the shell thickness.
First let me talk about the thickness of the shell. As I suspected – it depends on where you measure, but on average the sheet metal is about 0.020” thick. (The lowest was about 0.0185”). But after cutting through the thing, anyone worried about any 0.015” wall or greater, filter can exploding under even the worst oil overpressure run away, should well, relax a bit. Amsoil does not give one straight burst PSI to cover their filters, but the tech folks say minimum burst is 2x OEM rating on some up to 4x OEM on others. What is OEM burst strength (PSI), any way? Again as noted earlier I’d worry more about seams failing than the can bursting! (Read about at least one type with a thick can failing because the seam didn’t hold: Filter Study ) But both failure modes seem unlikely if the bypass is working.
The main worry with can thickness is FOD penetration. I sometimes worry when I run dual Motorcraft FL-1A’s on the 245Ti, because they are a bit exposed. They feel thinner (the minimopar study had them at 0.011” thick) so I feel better with the SDF-42/15 or the Mann….but a sharp object at xx or xxx mph….
Also the design does encompass a wound spring (vs. sheet metal spring) for by-pass. This seems more uniform – but maybe doesn’t matter much. If the filter does ever clog, the entire filter element will be pushed back indeed, (as most (?)) built in by-pass filters do. I don’t necessarily think ALL the filtered crap will go back into the oil stream, but still best to avoid clogging a filte...
Now for the meat of the thing: the filter element. Oops, too oily to inspect. Looks like it did it’s job. The media looks somehow thicker than other used filters I’ve cut into – but it’s difficult to say. The filter did seem to have less pleats than the equivalent Mann (Volvo OEM) - this doesn’t mean either has more surface area – maybe someday I’ll destroy some new filters!
I really, really wish I had a lathe to cut these things open.
First let me talk about the thickness of the shell. As I suspected – it depends on where you measure, but on average the sheet metal is about 0.020” thick. (The lowest was about 0.0185”). But after cutting through the thing, anyone worried about any 0.015” wall or greater, filter can exploding under even the worst oil overpressure run away, should well, relax a bit. Amsoil does not give one straight burst PSI to cover their filters, but the tech folks say minimum burst is 2x OEM rating on some up to 4x OEM on others. What is OEM burst strength (PSI), any way? Again as noted earlier I’d worry more about seams failing than the can bursting! (Read about at least one type with a thick can failing because the seam didn’t hold: Filter Study ) But both failure modes seem unlikely if the bypass is working.
The main worry with can thickness is FOD penetration. I sometimes worry when I run dual Motorcraft FL-1A’s on the 245Ti, because they are a bit exposed. They feel thinner (the minimopar study had them at 0.011” thick) so I feel better with the SDF-42/15 or the Mann….but a sharp object at xx or xxx mph….
Also the design does encompass a wound spring (vs. sheet metal spring) for by-pass. This seems more uniform – but maybe doesn’t matter much. If the filter does ever clog, the entire filter element will be pushed back indeed, (as most (?)) built in by-pass filters do. I don’t necessarily think ALL the filtered crap will go back into the oil stream, but still best to avoid clogging a filte...
Now for the meat of the thing: the filter element. Oops, too oily to inspect. Looks like it did it’s job. The media looks somehow thicker than other used filters I’ve cut into – but it’s difficult to say. The filter did seem to have less pleats than the equivalent Mann (Volvo OEM) - this doesn’t mean either has more surface area – maybe someday I’ll destroy some new filters!
I really, really wish I had a lathe to cut these things open.
