Car: 1981 Ford T-bird Oil: Super-Tech Synthetic 10W-30 Filter : Wix/Penske for the 1991 Ford Crown Vic Police w/ 5.8L V8 (smaller height) Problem: in less than 1000 miles, the oil filter appeared to be totally clogged and the oil that came out was pitch black and had the flow rate of mud. One of the fuel evap hoses from the carburetor HAD come loose and it was running rich for a few weeks. I'm not sure if this might have a lot to do with it. The oil filter came out and I tried to drain it - nothing came out. I let it set down on the floor (inverted so that the oil would drain to the bottom) but nothing drained out like it owuld normally drain. My 2000 Crown Vic had used SuperTech Synthetic 5W-30 for quite some time and the oil is still clear so I doubt its the oil quality that's the culprit. The 302 V8 in my T-bird HAD used 10W-40 throughout its life, and about 4 years ago I scooped out a bunch of sludge on the valley deck during my intake manifold R&R. The oil is always changed in 3 months/1000 miles with a new filter for the past 22+ years. This current oil has less than a month/under 1000 miles on it. Any ideas?