i believe 2006-2009 4.4 and 4.2 engines has different front strutsThe question is not in the the engine, the question is if you have adaptive dampening. If you do have adaptive dampening the the struts are the same for 2010- 2012... they are about $1200 State side. If you don't have adaptive dampening then the struts are the same for 2006-2012 no matter which engine you have... They are about $600 State side.
Side note, rear air bags are the same on all L322s from introduction to end of run. They easily out last 2 sets of front struts.