I have 97 Bravada and have had nothing but problems since we got it.Recently we had this shaking in the front whenever we acc.over 35 mph.So I rotated the tires and wallah it was a bad tire.Got it replaced then it ran good till recently I had a rebuilt transfercase put in.Got it back and the shaking came back.Rotated the tires again,but this time it didn't go away.The car is ok until I hit bout 45mph then it starts shaking again under acc.,get off the gas it's ok.Any advice would be greatly appreciated.