OKAY SO ive been trying to clean up my severly sludged 90 s15 jimmy 4.3 ive done like 4 200 mile changes this last change stayed in 3 months 900 miles oil was pretty dark i used 4 qts tech 1540 half qt tech 5-30 and 16 ozs mmo well oil came out ok but filter has a remote mount for it on driver side was full of what looked like black nasty thick oil but drain oil was cleaner filter was a fram toughgaurd 3980 what gives