I've been using Lucas in both my gas and diesel engines in my house. I've recommended it when I was a service manager. Lucas has been around for a very long time. Forrest started out making the oil additive for diesel engines and found out it just plain works well. The biggest thing the oil additive does is, it is a heavy additive and makes the oil return to the pan faster. I've used the injector cleaner in my new 08 2500HD diesel, no problems. It's been in my Corvette, my Harley-Davidson since I've owned them all.
So, yes, use it. No, not a snake oil. But like I told all my customers, and I'm sure you know too, there is NO "mechanic in a can".
The top end lube I really prefer is Marvel Mystery Oil added to the gas. I used it in all my VW based engines with great results.
BBTank