3406E/C15 .003" Undersized Spacer Plate

3406E/C15 .003'' undersized plate is recommended when your liner protrusions are too low to use the standard thickness plate. We use this plate 90% of the time. If you are changing the head with several miles on the engine, and not replacing liners, used liners tend to sink a couple thousandths after the engine has been built for sometime and this spacer plate will help get your protrusions back within spec.

We recommend using a new spacer plate with each overhaul. Lots of people decide to clean up the old spacer plate and reuse it but this is not a good idea. On the 3406E/C15 liner protrusion is crucial to making the head gasket last as long as the rest of the engine. If your liner protrusions are off just .0015 of an inch and then you use a old wore out spacer plate that may be off that same amount we guarantee you'll be back into the engine in a very short time. Don't let the cost of a spacer plate keep you from rebuilding the engine the right way. Once and done is cheaper than the time or labor to pull that head off again.

Key Functions and Benefits

• Stress Reduction on Liner Flange: The 1389381 plate is designed to minimize stress on the cylinder liner flange, which helps prevent cracking in the engine block.
• Precise Liner Protrusion: It ensures that the cylinder liners sit at the correct height (protrusion) relative to the engine block, enabling proper head gasket sealing.
• Engine Overhaul Essential: It is highly recommended to replace this plate during any major overhaul or when the cylinder head is removed to avoid premature, costly failures.
• Optimal Performance: By maintaining proper geometry, it prevents leaks and ensures the long-term reliability of heavy-duty trucks and industrial machinery.

• Part Number: 1389381 / 138-9381
• Compatibility: Caterpillar 3406E, C15, C15 Acert, C16, and C18 engines
• Thickness: Approximately 0.335 inches (0.003" undersized compared to some standard plates)
• Material: High-grade metal (durable casting)
• Engine Serial Prefixes: 1LW, 1MM, 2WS, 5EK, 6NZ, 6TS, 9NZ, BXS, MBN, MXS, NXS, SDP

• Trucking: Long-haul trucks equipped with Cat 3406E or C15 engines.
• Industrial Equipment: Various Caterpillar industrial machinery.

• Installation: Designed for direct fitment, but requires careful measurement of liner protrusion upon installation to ensure accuracy within 0.0015 inches.