1967 Triumph Spitfire 1.3L Petrol · MG 1380

The front suspension uses threaded brass trunnions that screw onto the bottom of the vertical links. Triumph specified EP90 hypoid gear oil for lubrication. In practice, owners and fast-fit garages pumped standard chassis grease into the nipples; grease hardens, dries out, and allows road grit to wear the threads. The trunnion seizes solid, causing metal fatigue that snaps the vertical link kingpin under steering load.

On Standard-Triumph four-cylinder engines—most acutely on the long-stroke 1493cc unit fitted to the Spitfire 1500—the semicircular copper-lead crankshaft thrust washers wear excessively. Repeated clutch disengagement pushes the crankshaft forward. Once thrust washers wear down, they drop into the engine oil sump; the unguided crankshaft then machines directly into the cast-iron cylinder block web, destroying the engine casing.

The Spitfire relies on a central double-backbone chassis with fabricated sheet-metal outriggers that support the outer sills and body tub. Road spray thrown from unshielded wheels rots the outriggers, floorpans, rear axle kick-ups and outer sills. Because the sill assemblies provide vital longitudinal stiffness to the open convertible body tub, severe rot causes structural flexing, scuttle shake, and sagging door gaps.