I change the oil using Valvoline for the very first time. I pulled a valve cover in the next oil change and was shocked again! The heads were completely void of sludge! That’s when I became a dedicated Valvoline user and have used it ever since. I run it in everything from Porsches, Corvettes, I use the VR1 in my flat tapped engines and have never had a problem in well over 50 years. Just change the oil and filter every 3k miles or so and the inside of the engine will be clean as new.
Pros: removes sludge, reliable for 50 years, keeps engine clean
Vehicle:
Chevrolet
