Sierra 18-1842 V6 Dry Joint Exhaust Manifold - Replaces 27-864850A02, 27-864547A1

The Sierra 18-1842 is a V6 dry joint exhaust manifold built for marine engines that use the dry joint manifold-and-riser exhaust configuration. Unlike a wet-joint design, the dry joint manifold moves water from the manifold to the riser externally rather than through an internal water jacket seal, which essentially eliminates the possibility of water entering the cylinders if a gasket fails. This makes it a common choice when reliability against gasket failure is a priority.

The 18-1842 is used together with the 18-1843 manifold and 18-1845 riser as a matched dry joint set, and it can also be used with the OE riser. It fits 4.3L, 5.0L, 5.7L, and 6.2L engines that utilize the dry joint manifold and riser system. The manifold has a white finish and weighs 33 pounds.

It directly replaces OEM manifold numbers 27-864850A02 and 27-864547A1, allowing it to be ordered as a drop-in replacement for engines originally fitted with those parts.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-1842
• Type: V6 Dry Joint Exhaust Manifold
• Fits: 4.3L, 5.0L, 5.7L, 6.2L engines utilizing the Dry Joint Manifold and Riser system
• Used With: 18-1843 Manifold, 18-1845 Riser
• Color/Finish: White
• Weight: 33 pounds
• OEM Cross-Reference: 27-864850A02, 27-864547A1

Fitment

Fits 4.3L, 5.0L, 5.7L, and 6.2L engines that utilize the dry joint manifold and riser exhaust system. Used with the 18-1843 manifold and 18-1845 riser.

Replaces (OEM)

• 27-864850A02
• 27-864547A1

Frequently Asked Questions

What engines does the Sierra 18-1842 exhaust manifold fit? The Sierra 18-1842 fits 4.3L, 5.0L, 5.7L, and 6.2L engines that use the dry joint manifold and riser exhaust configuration.

What OEM part numbers does the 18-1842 replace? It replaces OEM manifold numbers 27-864850A02 and 27-864547A1.

Is the 18-1842 the same as OEM part 27-864850A02? Yes, the Sierra 18-1842 is a direct replacement for OEM number 27-864850A02 as well as 27-864547A1.

What is a dry joint exhaust manifold? A dry joint exhaust manifold, like the Sierra 18-1842, transfers water from the manifold to the riser externally instead of through an internal water jacket seal, which essentially eliminates the possibility of water entering the cylinders if a gasket fails.

How much does the 18-1842 manifold weigh? The Sierra 18-1842 exhaust manifold weighs 33 pounds.

What color is the 18-1842 manifold? It has a white finish.

Can the 18-1842 be used with the OE riser? Yes, the 18-1842 manifold can be used with the OE riser in addition to the Sierra 18-1845 riser.

What other parts are needed with the 18-1842? The 18-1842 is designed for use as part of a matched dry joint set alongside the 18-1843 manifold and 18-1845 riser.

Does the 18-1842 require a specific gasket? The 18-1842 dry joint manifold is designed to work with the dry joint manifold and riser gasket system used in this exhaust configuration.

Why choose a dry joint manifold over a wet joint design? The dry joint design used in the 18-1842 essentially eliminates the possibility of water entering the cylinders if there is a gasket failure, since water is transferred externally from the manifold to the riser rather than through an internal seal.