Oil... Can I go from synthetic to non-synthetic?

[Salvatore]

Yes, It is formulated for diesel engines but can be used for anything. The additives are important. I also believe with the old style engine assemblies (gaskets and so forth) they do have a tendency to find some leaks with the thinner synthetic oils on the street. Just an observation. I use Amsoil for my automatic trans, rear and transfer case on my pickup. Has 144,000 miles on it and never had a trans or rear problem. (changed every 50,000) I use conventional motor oil 10W40 and never had the motor apart, and never use an oil additive. Some engine builders recommend the Rotella because it still contains some of the additives that the other oils had but have since been removed. It may be important for the flat tappet cams, but not as much for the roller cams. So.....