Can anyone answer if an exhaust leak can destroy your gas milage ?? I can hear the leak on passenger side rite near the manifold like air escaping or a ticking sound ...
My range gauge is reading so low now when the hummer tank is full and it use to read almost double when I'd fill the tank ?? Why is this stupid question maybe but I just don't get it !!

 

Yeah I don't think and exhaust leak would do that, but than again all that electronics could be telling the PCM that the truck is running lean and dumping more fuel in when it's not needed...

 

From my experience it does kill mpg, how much is another question. I am sure the exhaust leak is not helping the horse power either.

 

Yes I do believe it can make a difference. I'd get it fixed asap.