Three‑Piece Custom Transmission Tunnel Housing

For this project, DK34 Parts engineered a fully custom three‑piece transmission tunnel housing to integrate a modern automatic gearbox into a classic Toyota Land Cruiser. The original manual transmission was replaced with a contemporary automatic unit, which did not align with the geometry of the old drivetrain. To solve this, a completely new housing was designed — structurally strong, service‑friendly, and with a rugged 4x4 appearance that fits the character of the vehicle.

The housing consists of three individual modules that interlock seamlessly. This modular approach improves serviceability, enhances cooling, and delivers an OEM‑grade finish. The design is based on precise 3D scans and makes full use of the original mounting points.

This project demonstrates how custom engineering can upgrade a classic vehicle without losing its identity — blending modern functionality with timeless design.