Me. It had struggled to pass inspections the prior two years so in preparation I ran some Seafoam through it. Usually I change the oil the next day but I ended up driving it a couple more days. I left a dealership after bragging on it, reved it out in first gear on the feeder road and BOOM!!! Broke the crank at the front of the block; a connecting rod through the pan and a wobbly balancer is the result. This was about 2 years ago. If I had changed the oil, I would probably be at about 340k by now. Oh well, I have a 160k short block to replace it and a 306 block and pistons now to eventually build up for it.
Fortunately here in Fl there is no inspection, I wouldn't pass if they did. I change the oild like clock work n have replaced most part as needed with better aftermarket upgraded parts. Funny I remeber like it was yesterday when made my first MOD n after that I was hooked
Not really the seafoam itself, but I bet the seafoam helped some gunk work loose in the motor, it traveled to the oil pan and ended up clogging the oil pump intake. By me revving it up with reduced oil pressure, the crank did not like it!
I contacted Ford when I hit 200K with a letter and pics, and got a standard coorespondence back asking me what questions I had for them, and got some literature about the new Fords coming out. Then I was on their email list for service and rebates on new cars. So don't waste your time, Ford wants to sell new cars, not see how long one of their old Foxbody's last.
P.S. Just replaced my water pump a couple months ago, on my 3rd.