# 3855431 Gear Housing | Genuine Volvo Penta Part

## 🔧 Product Description

Genuine Volvo Penta gear housing from the Marine Propulsion group, weighing 17.599 kg and listed for 2 applications on SX series drives. It supersedes part number 3855084, which was catalogued earlier as a drive unit.

## ⚙️ Key Features

-   17.599 kg
-   SX series drives
-   2 applications
-   Supersedes 3855084, listed earlier as a drive unit

## 🔌 Function

Houses the drive's gears, shafts and bearings, holding them in alignment and retaining the gear oil.

## ⚠️ Common Signs of Failure

-   Milky or emulsified gear oil
-   Growl or whine from the lower unit
-   Swarf on the drain plug magnet
-   Impact cracks around the bearing bores
-   Bearings no longer holding tight in their bores

## 🛠️ Service Notes

-   The number it replaces was listed as a drive unit, so what was once ordered as a more complete assembly now comes as this housing - check what else your job needs before ordering
-   Gear housing 3855363 at 17.999 kg is only 400 grams heavier, so weight will not separate the two - order by part number
-   Nearly 18 kg and a freight item

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   3855431 → Supersedes 3855084

### OEM / Related Numbers

-   3855084 earlier number superseded by this part

## 📦 Condition

-   Genuine Volvo Penta part
-   Brand new
-   Supplied in original or equivalent packaging

## Details

- **Price:** 4542.0 AUD
- **Vendor:** Volvo Penta
- **Type:** Drives & Propulsion
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 4542.00 AUD | In stock |

## Images

- 3855431 Gear Housing | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/3855431-gear-housing-genuine-volvo-penta)
> Updated: 2026-10-10