The MGF rear suspension is built around Hydragas interconnected fluid-and-gas displacers rather than conventional coil springs. The geometry uses a rear lower arm, an upper arm, a forward-facing tie bar, and a track control rod to locate each rear hub, with the Hydragas displacer providing the springing medium. All of the locating arms and bushes here are MGF-specific, as the MG TF's coil-spring multi-link rear suspension uses different geometry and different parts.
Lower Arm, Tie Bar & Track Control Rod
The rear lower arm is a single MGF specification supplied complete with bushes, the inner bush at the subframe end being the same specification used elsewhere on the MGF front and rear lower arms, and the outer bush at the hub end MGF rear-specific. The tie bar assembly runs forward from each rear lower arm and controls fore-aft wheel location under braking and acceleration, supplied complete with bushes and support washers, requiring a thinner rear support washer and a thicker front support washer that are not interchangeable, as fitting them the wrong way round alters bushing preload and affects rear-end geometry. The track control rod sets static toe and is a separate adjustable item, and worn tie bar or track control rod bushes produce rear-end wandering and accelerated inner-edge tyre wear, so a check of these is always worthwhile when diagnosing unusual rear tyre wear patterns.
Anti-Roll Bar, Upper Arm & Ball Joint
The MGF rear anti-roll bar is a single specification, mounted to the rear subframe via clamp brackets and rubber bushes, with link assemblies connecting each end of the bar to a bracket on the rear hub, the links containing their own internal bushes and distance tubes, worn link bushes producing knocking from the rear over uneven surfaces. The link-to-hub bracket is handed and bolts to the rear hub, with mounting bushes, clamp brackets, and all associated hardware catalogued individually. On the MGF, the rear upper arm shares the same specification as the front upper arm, one upper arm serving both front and rear applications on each side, containing integral needle roller bearings and a grease nipple, with the pivot shaft changing during production at the same breakpoint as the front. The rear upper ball joint kit is the same specification as the front upper ball joint kit, a single MGF kit serving both ends of each side, distinct from the MG TF upper ball joint and not interchangeable.
Hubs, CV Joints & Bearings
The MGF rear hub is handed, and while early production distinguished between ABS and non-ABS specifications, current replacement hubs fit both applications. The outer CV joint has three configurations depending on ABS status and production date, pre-1D non-ABS cars using a standard joint on both sides, post-1D non-ABS cars using a standard joint on the right and an ABS-type joint on the left to provide the engine management with wheel-speed data for rough-road detection, and ABS-equipped cars using the ABS-type joint on both sides. The wheel hub and wheel studs are common with the front and with MG TF equivalents, and the rear hub bearing kit is the same specification as the front and as the MG TF equivalents, one kit covering all four corners, containing the bearing, the single-use stake nut which must never be reused, and the inner circlip. A polyurethane rear bush kit is catalogued as an MGF upgrade for more precise rear-end location and longer service life, with individual polyurethane sets also available for owners targeting specific areas rather than fitting the complete kit.