Sierra Gear Housing Seal Kit 18-2598, Replaces Volvo Penta 3855275

The Sierra Gear Housing Seal Kit, part number 18-2598, is a lower unit gear housing seal set for Volvo Penta stern drive and outdrive applications. The kit is built to renew the sealing surfaces of the gear housing where the driveshaft and related components pass through, helping keep gear lubricant contained and water out of the lower unit during service or a full gear housing rebuild. Using a complete seal kit rather than sourcing individual seals ensures every wear point in the housing gets fresh sealing material at the same time, reducing the chance of a repeat teardown from a seal that was left in place. The kit is finished in white and is packaged as a single set ready to install during routine lower unit maintenance. It directly interchanges with Volvo Penta part number 3855275, making it a straightforward replacement for that OEM number without needing to track down individual Volvo Penta seal components. This is a maintenance item for boat owners and marine technicians performing scheduled gear housing service, winterization teardowns, or repairs following a suspected water intrusion or lubricant leak.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2598
• Product Type: Gear Housing Seal Kit
• Application: Volvo Penta lower unit / gear housing
• Color: White
• Weight: 0.17 pounds
• Package Dimensions: 4.318 H x 11.938 L x 8.636 W (centimeters)
• Unit Count: 1 kit

Fitment

Fits Volvo Penta applications using OEM gear housing seal 3855275.

Replaces (OEM)

• Volvo Penta 3855275

Frequently Asked Questions

What does the Sierra 18-2598 Gear Housing Seal Kit fit? The Sierra 18-2598 kit is designed for Volvo Penta lower unit / gear housing applications and directly interchanges with Volvo Penta seal part 3855275.

Is 18-2598 a direct replacement for Volvo Penta 3855275? Yes, Sierra part 18-2598 replaces Volvo Penta OEM number 3855275, so it can be installed in place of that part without modification.

What is included in the 18-2598 seal kit? The kit is packaged as a single complete set of gear housing seals, sold as one unit count, rather than individual loose seals.

How much does the Sierra 18-2598 seal kit weigh? The Sierra Gear Housing Seal Kit 18-2598 weighs 0.17 pounds.

What are the package dimensions of the 18-2598 kit? The packaged kit measures 4.318 H x 11.938 L x 8.636 W in centimeters.

What color are the seals in kit 18-2598? The seals and packaging for the Sierra 18-2598 Gear Housing Seal Kit are white.

When should I replace my gear housing seals with kit 18-2598? Gear housing seal kit 18-2598 is intended for use during scheduled lower unit maintenance, a full gear housing rebuild, or after signs of water intrusion or gear lubricant leakage from the housing.

Is Sierra 18-2598 a genuine Volvo Penta part or an aftermarket equivalent? Sierra 18-2598 is a Sierra-branded seal kit built to replace Volvo Penta part 3855275, functioning as an aftermarket equivalent to that OEM number rather than a Volvo Penta-branded part.

Can I use kit 18-2598 on any stern drive lower unit? Kit 18-2598 is built for Volvo Penta gear housing applications specifically; it is not stated to fit other manufacturers' lower units.

Does replacing the seals with 18-2598 require a full lower unit teardown? Installing the Sierra 18-2598 Gear Housing Seal Kit is done during gear housing service, since the seals are located within the housing itself; the specific disassembly steps depend on the lower unit being serviced.