I put Luca's Low Viscosity Stabilizer in my 01 F150 4.6 which takes 5w-20 oil. It seemed to have some sort of bottom end noise for about half a second on startup due to the previous owner not doing oil changes frequently enough. My question is how long can I leave it in the crankcase? I usually change my oil every 3,000 since I don't drive much.
I personally don't recommend that product as I've seen it do more harm than good. It will quiet down the noise, but not fix the issue and sometimes it will even make it worse, including and up to destroying the engine.
If you have it added, standard procedure is to run it until the next oil change. So 3k miles would be when you swap it out by just doing a normal oil change.
Here is a link to additional information about the product:
https://bobistheoilguy.com/forums/threads/just-how-dangerous-is-lucas-oil-stabilizer.164890/
