I am actually more of a fan of SMB dollar tree products than Lucas. My dad put a bottle of Lucas in my engine when he changed the oil and now when I start it up after sitting for a few days there is smoke coming out of the exhaust. That could just be a coincidence, but before we had it in there the engine was in the same condition it was always in after he put it in there.
1992 Pontiac Bonneville 3.8 v6.155,440-STP 10w30
1992 Toyota Celica 1.6 I4. 290,726-Valvoline maxlife high mileage 10w30