Originally Posted by Shadetreeboy
Earlier today I emptied 70% of a quart bottle of Marvel Mystery oil into my crankcase. My Truck has NEVER sounded quieter!! I bought this thing about 1 month ago and immediately I started hearing VCT noises as well as "unknown" noises. These unknown noises would occur only sometimes and were louder at times than others. I am absolutly amazed at how quiet my engine is after putting this in the oil. I drove around town for 2 hours today to put the engine through all the rigors to make sure that I wasn't just coincidentally having a quiet engine day. Every 30 minutes or so I would pull through a bank teller window to see if the noises had returned. So far my 2005 5.4 liter has never been quieter and I am cautiously very excited about it. May not sell the truck afterall. I am concerned about leaving it in there tho. Can this stuff damage my engine?? Seals? Some people say only use it for a short time before an oil change. What do you guys think??
I've got some on my shelf, curious too!