[mdwilf]

Lucas makes some great products - the trans stuff & especially the power steering stuff is great - it's fixed some horrible seal leaks for me. The oil additive is OK for some things, if you have problems to fix, want to quiet down a noisy rear end, etc. But from my reading it doesn't have the chemicals to protect - there is a difference. I'm fairly convinced that if you want to protect things, your grandpa's STP oil treatment is the best bang for the buck to add the zinc & stuff.

Also, there is a huge difference in quality from oil brand to brand. I hope the pics show up. In the first one the motor had about 220,000 miles on it & had never had anything but Castrol in it for about 110,000 mi. You see how pretty & clean it is. Then I felt poor for a while & Pennzoil was on sale, so I bought a boat load of it. After only 60,000 more miles you can see how nasty the motor looked. Never used it since.

I found a great write up (I think on BTOG). Since I've lost the link, I'll summarize. If you believe that most wear occurs at startup, you then want the "clingiest" oil (so it stays behind after you shut down) and oil that flows well when cool so it gets where it needs the be as fast as possible when you crank it - synthetics win that contest hands down. Also, you want oil FLOW more than oil PRESSURE when your motor is running. The flow is what ensures lubrication, and dissipates heat more. You could have 60 pds of pressure because you are running 20w50, but if it takes forever for it to make it's circuit through the motor, it's not doing it's job.

Hope this makes sense, it's a great discussion about preserving the trucks we love. sorry for the long post.