Sierra 18-5105 Ignition Module - Replaces 3874020 - Chrysler Inboard 318, 340, 360, 440 Engines

The Sierra 18-5105 Ignition Module is an electronic ignition component built for Chrysler Inboard engines, restoring reliable spark control on engines originally equipped with a Chrysler electronic ignition system. It is designed as a direct replacement for the OEM Chrysler Inboard ignition module 3874020, making it a straightforward swap when the factory unit fails or ages out. The module falls under Sierra's Standard Ignition B.I.D. Electronic Ignition line for Chrysler Inboard engines, and is compatible with Chrysler Inboard 318, 340, 360, and 440 cubic-inch engines, as well as M318, M340, 360, and 440 marine engine variants.

Housed in a compact unit measuring 3.5 x 5.25 x 4.75 inches and weighing 0.97 pounds, the 18-5105 is sized to fit within the same mounting footprint as the original Chrysler ignition module it replaces. It ships as a single component ready for installation into the existing ignition wiring harness.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5105
• Product Type: Ignition Module
• Category: Chrysler Inboard Electronic Ignition Kit
• Replaces (OEM): 3874020
• Item Dimensions: 3.5 x 5.25 x 4.75 inches
• Weight: 0.97 pounds
• UPC: 030999318350
• Manufacturer Warranty: 90 days
• Compatible Engines: 318, 340, 360, 440 (1983-88); M318, M340, 360, 440 (1972-82)

Fitment

• Chrysler Inboard 318, 340, 360, 440 cubic-inch engines (1983-88)
• Chrysler Inboard M318, M340, 360, 440 cubic-inch engines (1972-82)

Replaces (OEM)

• 3874020

Frequently Asked Questions

What does the Sierra 18-5105 ignition module replace? The Sierra 18-5105 is a direct replacement for OEM Chrysler Inboard ignition module 3874020.

Which engines is the 18-5105 ignition module compatible with? It fits Chrysler Inboard 318, 340, 360, and 440 cubic-inch engines (1983-88), as well as M318, M340, 360, and 440 engines (1972-82).

How much does the Sierra 18-5105 weigh? The Sierra 18-5105 ignition module weighs 0.97 pounds.

What are the dimensions of this ignition module? The Sierra 18-5105 measures 3.5 x 5.25 x 4.75 inches.

Is the 18-5105 an OEM Chrysler part or an aftermarket replacement? It is a Sierra aftermarket replacement built to match the form and function of OEM Chrysler Inboard part 3874020.

What warranty comes with the Sierra 18-5105 ignition module? The Sierra 18-5105 carries a 90-day manufacturer warranty.

What ignition system does the 18-5105 belong to? The 18-5105 is part of Sierra's Standard Ignition B.I.D. Electronic Ignition lineup for Chrysler Inboard engines.

Does the 18-5105 include mounting hardware or just the module? The Sierra 18-5105 ships as a single ignition module component for installation into the existing Chrysler Inboard ignition wiring.

Can the 18-5105 be used on both older and newer Chrysler Inboard engines? Yes, it covers both the M318, M340, 360, and 440 engines (1972-82) and the later 318, 340, 360, and 440 engines (1983-88).

What is the UPC for the Sierra 18-5105 ignition module? The UPC for the Sierra 18-5105 ignition module is 030999318350.