The MGF and MG TF use four distinct subframe castings in total: an MGF front subframe, an MG TF front subframe, an MGF rear subframe, and an MG TF rear subframe. The front subframes differ between the two models because of the revised front suspension geometry and the MG TF's additional brace attachment points. The rear subframes differ much more substantially because the MGF subframe is designed around Hydragas displacers and double wishbones, while the MG TF subframe is engineered for the multi-link coil-spring rear suspension, completely different load paths and mounting locations. Subframes are supplied as bare assemblies, suspension components, brackets, and mounting hardware must be transferred from the original subframe during replacement.
For owners with badly corroded subframes, a complete replacement is usually more practical than attempting to repair individual corrosion pitting or mounting-hole damage.
Subframe Tower Plates, Sized for 15-Inch and 16-Inch Wheels
The subframe tower plates (the reinforcement plates at the top of each front subframe leg, distributing load into the bodyshell) are catalogued in two specifications: one for cars fitted with 6 × 15-inch road wheels (the standard MGF wheel size on most variants) and one for cars with 7 × 16-inch road wheels (Trophy, later MGF sports variants, and MG TF). Each specification is handed LH and RH. The 16-inch tower plates accommodate the increased loads and clearance of the larger wheel and tyre combination. Always confirm road wheel size before ordering tower plates.
Subframe Mountings, Rubber and Solid, with Production Variants
The subframe mountings are the most detailed ordering area within subframe service because of the combined mounting-type and production-breakpoint variations. Both the front and rear subframes have a front mounting and a rear mounting position, so four mounting positions in total per car. Standard MGF (non-Trophy) uses rubber mountings at all four positions. Within the standard MGF range, early cars (to VIN WD26658) used one original rubber specification; cars from VIN WD26659 onwards use a revised rubber specification (current service item).
The earlier mountings on an MGF up to WD26658 may be replaced with the later mountings, but both front and rear mountings must be updated together as a pair, mixing old front mountings with new rear mountings (or vice versa) produces mismatched compliance and an unbalanced ride character. MGF Trophy and all MG TFs use solid mountings in place of rubber at all four positions. This specification was introduced on the MGF Trophy and carried over to all MG TF production, creating a useful parts commonality between Trophy MGFs and MG TFs. The solid mountings eliminate the rubber compliance that standard MGFs exhibit, producing more precise dynamic response at the cost of slightly increased noise and vibration transmission into the cabin.
Mounting Bolts, Matched to Mounting Type
Because the rubber and solid mountings are different heights and use different bolt lengths, the mounting bolts are also different specifications. Three mounting bolt specifications exist: an early bolt for standard MGFs to WD26658, a later bolt for standard MGFs from WD26659 onwards (the current rubber-mount specification), and a different bolt for MGF Trophy and MG TF (the solid-mount specification).
When ordering mountings, order matched bolts at the same time, fitting new mountings on old bolts often produces an incorrect clamping load and stripped threads.
Upper Side Members
The upper side members (the bolt-in structural rails above each subframe) are catalogued as handed items. The rear subframe upper LH side member has three production variants: an MGF specification to VIN XD511058, a revised MGF specification from VIN XD511059 (MY2000 facelift), and a dedicated MG TF specification. The RH upper side member is a common specification across models. All side members bolt to the subframe with specified screws; bush items included with the side members are separately catalogued where they are replaceable.
MG TF Subframe Braces
MG TF cars are fitted with additional front subframe braces that further stiffen the front subframe structure, these are not fitted to MGFs. Two production variants exist: an early specification for MG TFs to VIN 3D618325 and a revised specification from VIN 3D618326 onwards. Each is handed LH and RH.
When ordering for an MG TF, confirm the VIN against the 3D618325/3D618326 breakpoint.
Snubber Spacers and Lower Arm Cup Spacers
The snubber spacer sits within the suspension mounting path and limits extreme travel. The lower arm cup spacer is catalogued in a single specification that fits MGF from VIN AD000506 onwards and all MG TFs, earlier MGFs used a different arrangement.