Doesn't the G54B engine have a timing chain instead of a belt... But that probably needs to be replaced anyway. I plan on giving a full tune up in the next couple months but money's tight right now with the holidays... I find that it is getting around 14 - 15 mpg is that bc its a 4x4 and it eats more gas or will a tune up improve that?

Thanks for the help, i look foward to driving this truck till it dies and then bringing it back to life