The Chevrolet Silverado offers a variety of body styles and powertrains that allowed it to serve as a utility vehicle and the family car. Chevy introduced Silverado in 1999 and many of those vehicles are still on the road. The following steps guide you through the removal and installation of the intake manifold on the 1999 and 2000 models.
Disconnect the negative battery cable. Relieve the pressure in the fuel system, then remove the air intake duct. Pull the throttle cable and the cruise control line from the throttle body.
Drain the cooling system (see Warnings). Remove the drivebelt and the secondary air injection crossover pipe. Label the vacuum hoses and electrical connectors and disconnect them from the intake manifold. Disconnect the electrical connectors from the air conditioning compressor as well as the alternator.
Locate the ground strap and remove it from the back of the right cylinder head. Pull the wiring harness brackets and set the harness to the side. Remove the upper radiator hose, the coolant bypass hose and the heater hose support bracket. Disconnect the heater hoses from the engine.
Label and disconnect the spark plug wires then remove the distributor. Remove the EGR pipe from the intake and exhaust manifolds. Disconnect the fuel feed and return lines.
Loose the nut that holds the power steering pump to its rear bracket, then remove the lower nut that holds the front of the pump to the bracket. Remove the bolts that hold the power steering pump bracket to the front of the engine and push the bracket forward to allow access to the front intake manifold bolt.
Loosen the intake manifold bolts in quarter-turn increments, using the reverse order of the tightening sequence. Break the gasket seal.
Lift the manifold from the engine. Check to make sure that all connections have been removed from the manifold.
Clean the mating surfaces of the cylinder heads, block and manifold. Use aerosol gasket removal solvent according to the manufacturer's instructions.
Take a gasket scraper to remove sealant or gasket material, then clean the surfaces with solvent. Clean the threads in the bolt holes.
Apply a bead of RTV sealant 3/16 inch wide to the front and rear manifold mating surfaces. Position the gaskets on the cylinder heads so that the ears overlap the beads of RTV sealant. Be sure to position the gaskets with "this side up" visible.
Align all intake port openings, coolant passage holes and bolt holes correctly. Bent any gasket tabs over so that they are flush with the rear surface of each cylinder head.
Set the manifold in place while the sealant is wet. Tighten the bolts in sequence, making three passes on each.
Reconnect all lines, hoses and electrical connectors in the reverse order of removal. Reconnect the negative battery cable. Refill the coolant system with the correct type and amount of coolant.
