Here are 2 PH5s from my 93 C1500 5.7l running QS blend HM 10w40 and HPL EC30. Filters have 36 even pleats, silicone ADBVs and filter material is right at 42"long. 1st filter has 1382 miles on it. Only saw one little piece of crud in the pleats but down in bottom looks like, what I would assume to be some liquefied sludge and varnish. Second filter has just over 2k miles on it-forgot to write down the exact miles, it does have some of the dark sludgy looking residue in the can but I did punch a hole in the side of the filter and let it drain as the first one took forever to drain the oil from the pleats. It may have had the same amount but I will never know. One thing I have noticed the motor has developed a valve cover gasket leak on the driver side at the rear of the motor. So maybe the EC cleaned up some goo that was plugging the leak idk . Will have it fixed when I get the truck back from my son. Also noticed some oil seepage around the PCV and Breather grommets in the valve covers, one on each side.
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