MDOT has a great resource to help you avoid sitting in traffic due to the usual summer road construction. There is a plain text version as well as an interactive Flash version of a map showing major road and bridge construction (or is it destruction?) projects on state roads as well as the interstates that crisscross Michigan. The map gives the tentative dates for the construction as well as what to expect as far as lane closures and detours. I find that it is well worth the time to try and avoid wasting the ever more expensive gasoline in our tanks by sitting in traffic. This allows you to seek alternate routes that just might (gasp!) make you slow down and enjoy the beautiful state of Michigan that you are traveling through.
You can find the map at the MDOT page at Michigan.gov. Also, there is a regularly updated listing of lane closures (which will most likely be more current than the MDOT map) that you can view here. The lane closure map allows you to search by region, county, routes, and filter it by date.