When installing a cylinder head on your 2000 Chevrolet Impala with the standard 3.4-liter V-6 engine, apply thread sealer to the head bolts. Tighten them in the correct sequence to 37 foot-pounds, and then turn the bolts an additional 90 degrees.
With the head set in front of you, number the head bolts clockwise, starting from No. 1 in the upper left corner -- 1 though 4 on the top row and 8 through 5 on the bottom row. Tighten the bolts in this sequence: 7, 2, 3, 6, 8, 1, 4, 5.
