I want to put full sythentic oil in my car, is it true that once you put sythentic oil in you have to keep puting it in as long as the car lives ?

 

no, this is not true. you can switch back over to conventional. however when u make the switch either way u will probably want to change it again sooner than you normally would the first time. with synthetic, you can lose some oil because more of it will absorb into the little nooks and crannies of ur engine, so check the level shortly after the change. switching back i have heard you can get a little more gunk coming out, so just change it again after 1500-2000 miles instead of the normal 3k

 

Thanks for the help.