🔩 Centre Coupling – Leyland L/L Tusker (L/L 350 / L/L 370)

📌 What It Is

The centre coupling — also called a centre joint coupling flange — is a driveline component used in multi‑section propeller shafts on heavy trucks. It connects two halves of the drive shaft or links the intermediate shaft to the main driveshaft, allowing rotational torque to pass smoothly while accommodating slight misalignment and movement of the driveline as the vehicle operates. It is especially used in long‑shaft vehicles like Leyland Tusker where a centre bearing and coupling are needed.

⚙️ Typical Specification for Tusker

According to automotive parts catalogs (propeller shaft & coupling flange listings):

Application: Centre Coupling Flange for Leyland L/L Tusker family (L/L 350 / L/L 370).
Part Reference (Aftermarket): CF 745 — Centre Coup. L/L Tusker (OEM ref F1430211).
Splines: ~10 splines — positive torque transfer interface.
Plate Type: Typically square flange (though both round and square couplings are used depending on shaft type).
Plate Diameter: ~150 mm (approx — 6″ class).
Bolt Pattern: 4 bolt holes for secure fitting to driveline yokes/shafts.
Bolt Size / Plate Thickness: Typical 12.80 mm thickness, 21 mm bolt size class.

👉 This flange is designed to mate with the corresponding centre propeller shaft yoke or intermediate coupling assembly, completing a rigid but flexible driveline connection.

🛠️ Function in the Driveline

The centre coupling flange serves these main purposes:

✔ Torque Transmission: Carries rotational power from the front section of the propeller shaft to the rear section (or vice versa) in multi‑piece shafts.
✔ Alignment & Movement: Allows small angular and axial movements between shaft sections, especially over uneven terrain or suspension travel.
✔ Vibration Damping: Helps reduce vibration and shock loads transmitted down the driveline — increasing longevity of components and improving ride comfort.

🚚 Where It Fits

In a Leyland L/L 350 / L/L 370 Tusker with a multi‑section propeller shaft: