The rear suspension uses a conventional live axle on semi-elliptic leaf springs, a tried and tested arrangement shared in principle with virtually every British car of this era. The rear springs themselves differ between the TD and TF, but the shackle hardware, interleaf pads, U-bolts, bump rubbers, rebound straps, and shock absorber arrangements are common between both models.
Rear Springs
The rear leaf springs are model-specific: the TD and TF each have their own catalogued spring, reflecting the different weight distribution of each model. Both springs are multi-leaf semi-elliptic units supplied complete with a Silentbloc bush at the front (fixed) eye. The Silentbloc bush itself can be replaced individually if the spring leaves are otherwise sound. Spring assembly bolts, distance tubes, and locking nuts are available in both BSF and Unified thread as alternatives, either thread can be fitted to any car.
Synthetic interleaf pads are available to place between each pair of spring leaves, reducing inter-leaf friction and eliminating the squeaking that develops as original interleaving breaks down. Fresh interleaf pads make a noticeable improvement to ride quality and to the spring's responsiveness.
Spring Mounting
Each spring is fixed at the front eye to the chassis by a front spring mounting bolt with fibre washers, a single bolt locating the spring eye to the chassis bracket, with the Silentbloc bush in the eye allowing the spring to articulate. The rear eye of each spring is shackle-mounted to the chassis to accommodate the change in spring length as the suspension articulates. The shackle assembly at the rear of each spring comprises four shackle plates, eight rubber bushes, and four shackle pins per car, with the corresponding spring washers and nuts. The shackle bushes are the primary wear item and deteriorate progressively with age, allowing excessive axle movement that manifests as rear-end wander and a clunking noise over bumps.
Axle Mounting and Damping Components
The springs are clamped to the rear axle by U-bolts passing through spring plates, with rubber spring pads cushioning the axle on the spring upper face. A buffer plate, an MGA item now widely used as a recommended modification for the TD and TF, distributes the U-bolt clamping load and prevents the U-bolts from indenting or cracking the axle case under heavy braking and acceleration. Bump rubbers at each side prevent metal-to-metal contact at full suspension compression, and rebound straps prevent the axle from dropping far enough at full extension to damage the brake hoses. The bolts securing the bump rubbers and rebound straps to the chassis are common items.
Rear Shock Absorbers
Hydraulic lever-arm shock absorbers are fitted at each rear corner, mounted to side-specific brackets bolted to the chassis. Both Girling and Armstrong shock absorbers were used during production, and both manufacturers' units are reconditioned on a customer's own unit basis, supplied as side-specific (right-hand and left-hand) items. The mounting hardware differs entirely between the two manufacturers: separate chassis bolts are catalogued for Girling and Armstrong, and the link arrangements are quite different. The Girling link is supplied as a separate component with separate bushes, pins, and a dedicated installation tool set required to press the bushes into the link.
The Armstrong link is supplied complete with its fixings, bolts, nuts, and washers, and does not require special tooling to install. When ordering rear shock absorbers, the manufacturer must be identified, the chassis mounting bolt pattern and the link-to-axle connection are not interchangeable between Girling and Armstrong. Mixing the two specifications within the same car is not possible without modifying the link or bracket arrangement.
Ordering Considerations
The model, TD or TF, determines the leaf spring specification. The shock absorber manufacturer (Girling or Armstrong) determines the mounting bolt pattern, link assembly, and installation hardware. Most other rear suspension components, shackle hardware, U-bolts, spring plates, spring pads, bump rubbers, rebound straps, interleaf pads, and the Silentbloc front eye bushes, are common across both TD and TF and require only quantity confirmation when ordering. Spring assembly fixings can be ordered in either BSF or Unified thread to suit the owner's preference.
The buffer plate modification is recommended whenever the spring U-bolts are disturbed for any reason.