The last two filters I bought at my local Mazda dealer were Value Line filters, and before I put them on, as usual I wiped the inlet holes and machined threads with an oil damped paper towel and both of them had sizeable metal flakes in the threaded area, so much that I contemplated stopping right there and going to Autozone or wherever get a different filter but it was late in the evening both times and was filthy and had no real way to do this. I wiped them down until I could see no more flakes and used both of them. Box of these were Mexican made. One of the flakes was alarmingly large.
I went in last week to get another filter and this time they gave me a Thailand made filter. This one had no metal flakes at all and the inlet holes and metallic surfaces were pretty clean. I had no problem using it and was a bit relieved it wasnt like the previous two.
When I was checking out with the cashier, someone else came in and was talking to the parts guy about filters, and though I was dealing with the cashier and talking to her I distinctly heard him say "yea we have had some issues with those filters so we switched to these". Maybe this guy noticed the same thing I did, I dont know. It was kind of busy and I only caught bits and pieces of what they were saying. I know the service manager there and was going to talk to him about it but he was being yanked every which direction so I didnt get to talk to him. I plan to stop in and ask him about it if I get time in the next few days.
