Frame And Members problems of the 2006 Chevrolet Uplander

Bought a 2006 Uplander from royal Chevrolet in richmond va. Vehicle was sold to us in July 2007 as new. Starting in oct-Nov vehicle engine light comes on, in November tie rods and sway bars had to already be replaced, vehicle vibrates while sitting still,vehicle steering column creaks, clanks and screeches, vehicle sways to right and I have to "overdrive" to keep it on road safely, shakes while sitting still, rattling noise from right side back passenger area, headlight dim on their own while driving at night, rpms rev up with normal driving,gas reads empty with 1/4 tank in it and will not start if parked on downward incline. The only thing taken seriously was the tie rod and sway bars, they were fixed but van still shakes and does not feel safe. I wrote letters to the manufacturer and many weeks have gone by with no contact from them to help me fix my problems.