red_loctite
Full Member
hey folks. I have heard from a mechanic friend of mine to be careful of running synthetic oil in my 5.3. I am in Calgary AB wehre it can get to -40c in the winter. I drive highway 250kms a day or about 40000kms a year. I will have to have the trans rebuilt this year but i don't want to worry about the engine. i have 220000kms on it now. i will be doing plugs shortly, and fuel filter. my mechanic friend was saying the 5.3 run rougher on synthetic oil. any thoughts?
chris
chris