# 3979035 Gear | Genuine Volvo Penta Part

## 🔧 Product Description

Genuine Volvo Penta gear from the Marine Propulsion group, weighing 1.078 kg and listed for 4 applications across the THD and DH series. It supersedes part number 425996.

## 🚤 Compatibility

Typically suits:

-   Volvo Penta THD102KB
-   Volvo Penta THD102KD
-   Volvo Penta THD102K-KB
-   Volvo Penta DH10A

-   **Engine Family:** THD, DH

## ⚙️ Key Features

-   1.078 kg
-   Supersedes 425996
-   4 applications across the THD and DH series
-   Marine Propulsion group

## 🔌 Function

Transmits drive from one shaft to another through meshing teeth, setting the speed and torque relationship between them.

## ⚠️ Common Signs of Failure

-   Whine or growl that changes with load
-   Teeth chipped, pitted or worn to a point
-   Metal glitter in the oil or on the drain magnet
-   Backlash felt to be excessive when the drive is rocked
-   Bore or keyway worn so the gear moves on its shaft

## 🛠️ Service Notes

-   Inspect the meshing gear and the bearings at the same time — a damaged tooth flank rarely happens alone
-   Renew the oil and clean the housing before reassembly so no debris is carried over

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   3979035 → Supersedes 425996

### OEM / Related Numbers

-   425996 earlier number superseded by this part

## 📦 Condition

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

## Details

- **Price:** 1017.85 AUD
- **Vendor:** Volvo Penta
- **Tags:** Volvo Penta

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 1017.85 AUD | In stock |

## Images

- 3979035 Gear | Genuine Volvo Penta Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/3979035-gear-genuine-volvo-penta)
> Updated: 2026-08-22