I was wondering if I need to have a oil change or does my 05 Trailblazer suck up gas. I start my day with a full tank of gas and drive 70 miles roundtrip and I may eat up about half a tank of gas.

A oil change won't help that problem you should have a shop scan it to see if there's any other problems.you should be changing your oil every four to five thousand miles. .

That a problem i have a 2004 trailblazer and i get about 300 miles per tank give or take a few miles.

My 2005 Trailblazer bounces on the interstate when i do the speed of 60 to 65 it wobbles pretty badly i have to knock it down to 55 in certain areas talking bout Embarrising what can i do.

My 2005 Trailblazer want to turn off on ever stop