Tires, Front Bumper Cover, and other questions...

[Two 9-3s]

Good afternoon! I have a couple questions since I am embarrassingly ignorant about much of what goes on with my 2010 Saab 9-3.

1. Issue I have with my tires: two front tires are at 4/32nds and back tires are super choppy, but have 7/32nds. Is it safe to just put the 4/32nds in the back and get two new tires (they will replace the choppy ones) and put them on the front? Will I have over steering issues with new tires in the front and worn out tires in the back? Will it even be safe? Should I just buy four new tires?
-Any tire recommendations as well? 215/55r16's is what I will need. I don't really want to spend $130-$140+ on tires so I was thinking about going with generals.
2. I have a pretty bad crack in my front bumper cover + the plastic underneath (I think its like an air shield or something?) I have been actively looking for a used replacement. Any idea where I can find one? I don't want to spend the $500-600 bucks quoted to repair if I can get a replacement for the same price.

Thanks

Andrew

[Digger]

http://car-part.com/ My first go to place for used parts and should score you the parts you need.

Best advice on tires is make sure your rear wheel alignment bolts aren't seized in the toe links before you get new tires. Sounds like you need a wheel alignment and if you need new parts best to get them before you go to the alignment rack where every bolt that breaks adds an extra hundred to the cost of getting the job done.

[swisssaabist]

A part from excellent advices from Digger i will say you need to must doing 4 wheels when you've to realign your driving quotes, try to find an electronic one the service man there could unbolt rear ones and adjust the play even if it's not possible from the manufacturer.
i know how the temptation was huge that choosing cheap tires but finally it ain't worth it,
first that you have only the surface of 4 postcards in contact with road .. second they are less efficient when it comes to brake and 2m less could save a life, without choosing premium ..i'm sure you can find it ..that's my 2 cents.