This section covers the individual front suspension components, coil springs, wishbone arms and inner pivot bushes, trunnion assemblies, bump stops, and front shock absorbers with mounting hardware, the parts that wear in service.
Coil Springs and Spring Seats
Front coil springs are common to TD and TF and to LH and RH sides. The springs locate on spigots at the lower end (shared with the MGB front suspension), sitting in spring pan seats secured to the lower wishbone by screws, washers, and nuts. Springs should always be replaced in pairs to maintain equal ride height. Sagged springs cause the front to sit low and reduce bump travel.
Wishbone Arms and Inner Pivots
Each side uses four wishbone arms (two upper, two lower) pivoting on the chassis crossmember through inner bushes on the wishbone pivots. The standard arm is supplied "not pierced for anti-roll bar fitment", the TD/TF crossmember is not drilled for an anti-roll bar (a conversion would require pierced arms from a later model). Wishbone pivots are supplied in Unified thread and may be fitted to BSF cars with matching Unified nuts. Pivot-to-chassis bolts, spring washers, and nuts (nyloc and stiff) complete the inner pivot.
Wishbone inner bushes are the primary wear item. Three specifications are available: original-fitment rubber, road polyurethane, and race polyurethane. A heavy-duty one-piece alternative (from the MGB V8 specification) is available for hard use. Retaining washers, slotted nuts, and split pins complete the assembly.
Worn bushes allow geometry to shift under braking and cornering, causing vague handling and uneven tyre wear, the difference replacement makes is often striking.
Trunnion Assemblies
The upper and lower trunnions provide the steering pivot and vertical articulation. Each comprises a body with bush, a greasing plug, grease nipple, and swivel-pin-to-trunnion seal. The bottom trunnion is also available as a pre-assembled Unified unit, fittable to earlier BSF cars. Trunnion bolts come in BSF (TD to chassis 12284) and Unified (TD from 12285, all TFs).
The internal seal arrangement includes top and bottom trunnion seals, supports, thrust washers, distance tubes, and split-pinned slotted nuts. A complete kit (eight trunnion seals plus four swivel pin seals) refreshes both sides at once. Trunnion bushes wear over time, especially with a neglected greasing regime. Worn bushes give a clunking noise over bumps and looseness felt at the wheel.
New bushes can be pressed into the bodies, but the bore should be checked for ovality first, a worn body will not support a new bush correctly and should be exchanged.
Bump Stops
Front bump stops limit upward travel, preventing coil bind and tyre-to-inner-wing contact under heavy compression. The current specification requires an alloy spacer between bump stop and chassis, the earlier type without the spacer is no longer available. Bump stop and spacer are secured at each side by two bolts, two nuts, and spring washers, with a screw and additional washer. Hardened or cracked bump stops should be renewed, the rubber compound deteriorates with age, oil exposure, and UV light.
Front Shock Absorbers
Front shock absorbers are hydraulic lever-arm units, available in Armstrong and Girling original specifications on a customer's own unit reconditioned basis. The damper arms act as the upper wishbones, a Y-type-derived feature carried into the MGA and MGB, so damper condition directly affects ride quality and upper geometry. A worn damper not only affects damping but allows lateral play at the upper pivot. Mounting bolt kits are matched to Armstrong or Girling, the two are not interchangeable, with different bolt patterns.
The TD Mark II also had adjustable Andrex friction shock absorbers at all four corners alongside the hydraulic units, for competition use. Originals are not catalogued, but Mark II owners restoring to full original specification should be aware that the friction dampers are part of the period-correct setup.
Ordering Considerations
Coil springs, spring seats, spring pan hardware, wishbone arms, inner bushes, bump stops, and shock absorbers are common between TD and TF. Trunnion bolts and slotted nuts are thread-specific (BSF to chassis 12284, Unified from 12285 and all TFs). Specify Armstrong or Girling when ordering a shock absorber, the bolt kits are matched to the damper type. Bushes are ordered in pairs or in complete sets of eight (four arms per side, both sides).
Trunnion seal kits cover both sides simultaneously.