BigT hit the nail on the head. Not really needed. If you felt obliged to use something, use a concentrated complete fuel system cleaner every 60,000 miles or so. Something like Redline SL-1.
Add it to an empty tank as you FILL up all the way. Add it to the last full tank of gas you'll have prior to an oil change. Drive through the whole tank, and then change your oil out.
Fuel naturally gets into your oil during the combustion process, and you don't want the fuel system cleaners circulating through your oil for thousands of miles. Won't really harm much, but it's not good either
