Instruction Manual

INS 116

1996-2004 GM 5.0/5.7/4.8/5.3/6.0L

Full Size Truck Headers

Part#s 4005/0,4006/0,4007/0

Step 1

Disconnect the negative battery terminal and allow the engine to cool.

Step 2

From beneath, remove the nuts that attach the Y-pipe to the factory exhaust

manifolds.

Step 3

Unbolt and remove the factory exhaust manifolds and the stock gaskets.

Step 4

Clean any old gasket material off of the cylinder head. Use a scraper if necessary.

Step 5

Using the factory stock hardware and the supplied gaskets install the BBK headers.

Step 6

Using the factory stock hardware and the supplied gaskets, attach the Y-pipe to the

BBK headers.

Step 7

Using the supplied hardware, gaskets, and block-offs connect the EGR and AIR

fittings to the BBK headers where applicable

Step 8

After driving the vehicle and allowing it to cool a few times, go back and retighten the

header bolts.