I just swich sae oil for synthetic oil, some people said is good and other is not whit older engine. I' m confuse and I dont know what to do ?
You'd be better off sticking with regular petroleum based oils. Unless your engine is a fresh rebuild, you will not see many gains from the switch. You may also find that your engine will develope a few new leaks. Do a search in the forums for "oil" and I am sure there are quite a few threads on this already. Mike
There is no problem with using synthetic oil in your Buick. Like Mike said you may or may not notice some leaking from the engine. If you have an engine with leaky gaskets, they may leak a lttle more. Synthetic does everything better than conventional oils. By Law, all motor oils must be compatible. You can switch back if you want, I wouldn't. Leave it in.