Mitsubishi V4A5 / V5A51

Mitsubishi's rear-drive automatic — in the Pajero and Shogun.

These are working four-wheel-drive vehicles and heat is what shortens the transmission's life. Towing and low-range use put load through the torque converter rather than the gearbox, and the fluid pays for it first — which makes an auxiliary cooler a preventative measure rather than an accessory.

Its recurring complaint is a shudder or a slip that appears hot and loaded and disappears when it is not — the lock-up clutch, and a fluid-condition symptom before it is a mechanical one.

Where genuine wear appears it is the direct clutch and the overdrive band, presenting as a flare on one change under load. Catching it early is the whole difference, because a slipping clutch fills the fluid with what it is shedding.

Fluid is Mitsubishi's Diamond SP-III and the interval is real whatever the handbook implies; on a vehicle used for towing it is shorter than the book.