The front suspension of the TD and TF is the independent coil-spring and double-wishbone arrangement carried over from the MG Y-type saloon, a layout that proved so successful that it continued through the MGA and MGB until the end of MGB production in 1980. The unequal-length wishbones pivot on the chassis crossmember, with coil springs sitting on lower spring seats and the front shock absorber arms acting as the upper wishbones. The stub axle assembly is connected to the wishbones through upper and lower trunnions, providing both the steering pivot and the vertical suspension articulation.
Front Suspension Components
The Front Suspension sub-section covers the coil springs, wishbone arms and pivot bushes, trunnion assemblies, trunnion seal kits, bump stops, and the shock absorber mounting hardware. The wishbone inner bushes are the primary wear item in the front suspension and are the most commonly replaced component, available in original rubber, road-specification polyurethane, race-specification polyurethane, and a heavy-duty one-piece alternative derived from the MGB V8.
Stub Axles and Hubs
The Stub Axles and Hubs sub-section covers the stub axles themselves (available in both BSF and Unified thread on a customer's own unit reconditioned basis), swivel pins, trunnions with bushes, steering arms, front hubs and brake drums, wheel bearings, grease retainers, hub oil seals, and wire wheel conversion components. The front hub and brake drum assembly is one of the most chassis-number-dependent components in the catalogue, with four distinct specifications across the production run reflecting changes to the hub casting, grease retainer arrangement, and thread type.
Lubrication Regime
The TD and TF front suspension was designed for a regular lubrication schedule that modern owners may underestimate. Each side carries multiple grease nipples, at the trunnions, the steering arms, and the swivel pin assembly, that require attention every few hundred miles to prevent premature wear of the trunnion bushes and swivel pin bearings. A neglected lubrication regime is the most common cause of front suspension looseness and wear, and any rebuild should be accompanied by a commitment to maintain regular greasing thereafter. The front suspension grease points are detailed in the original handbook and covered under Service & Lubrication.
Ordering Considerations
The chassis number determines the BSF or Unified thread specification for trunnion pins, swivel pin nuts, and steering arm fixings (BSF to chassis 12284, Unified from chassis 12285 through all TFs). The wheel type, steel disc or wire, determines the front hub and brake drum specification. Coil springs and most front suspension wear items are common across both models. A complete trunnion seal kit covering eight top and bottom trunnion seals plus four swivel pin to trunnion seals is available, providing the most economical way to refresh the front suspension seals on both sides simultaneously.