Got a break from changing the widow's oil, so thought I would post...
Thanks for the feedback on the 01 PT. I really wanted to use the M1 in it as I have read so much good about it, so I am thinking of running the Havoline with some AutoRx and see what we get. We bought it used with 50k on it, so you may be right, it may have knocked some crud loose inside. The Neon we bought with only 18k loves the M1, so you may be onto something. If the Havoline quiets it down, I may try M1 later in the summer and see what happens after 2 cleansing oil changes.
And on the E-Core design, I was just joking. I had read another post that was debating the merits of it, and everyone was very passionate about whatever side they were on. I like the Supertech filters myself (for the price), but the $1.01 Purolators at PB were just too good a bargain to pass up.