Both the MGF and MG TF use electric power-assisted rack-and-pinion steering (EPAS), making them among the earliest volume production cars to adopt this technology, predating the widespread adoption of EPAS in mainstream cars by several years. The EPAS system uses an electric motor to provide variable assistance based on road speed, with high assistance at parking speeds for manoeuvrability and progressively reduced assistance at higher speeds to maintain steering feel and feedback. Unlike hydraulic power steering, EPAS imposes no parasitic load on the engine when assistance is not being called upon, contributing to marginally better fuel economy and eliminating the need for a hydraulic pump, fluid reservoir, and associated pipework, one fewer set of items for owners to maintain. On the MGF, EPAS was standard equipment on VVC models from the September 1995 launch, and on the 1.8i from the start of the 1998 model year (mid-1997 production), earlier 1.8i cars were offered with manual steering or EPAS as an option. The MG TF had EPAS standard across every variant from launch, with no manual-steering option.
Rack Ratio, The Most Noticeable Difference When Driving
The steering rack ratio is one of the most immediately noticeable differences between driving an MGF and an MG TF. The MGF rack provides 3.1 turns lock-to-lock with a turning circle of 10.5 metres kerb-to-kerb, a relatively relaxed ratio appropriate to the MGF's softer suspension character. The MG TF rack was regeared by approximately 10 per cent to provide 2.8 turns lock-to-lock with an overall ratio of 17.5:1 and a broadly similar turning circle. The faster MG TF gearing matches the car's sharper suspension and delivers the more responsive, direct steering feel that complements the revised chassis.
MGF and MG TF steering racks are not interchangeable because of both the different ratio and mounting differences.
Steering Column Adjustability
The MGF steering column in its original 1995 to 1999 specification offered limited adjustment. The MY2000 facelift introduced an adjustable column providing height adjustment to accommodate a wider range of driving positions, and this improved column specification was carried over to all MG TF production. Column adjustability is one of several small improvements that distinguish MY2000+ MGFs and all MG TFs from earlier MGFs. The steering wheel diameter is 355mm across both models.
Diagnostic Notes
Worn track rod ends produce vagueness at straight-ahead and wandering on motorways, a free-play check at the wheel with the car stationary identifies them reliably, and replacement should always be followed by a four-wheel alignment. Worn intermediate shaft universal joints produce a knocking or clunking sensation through the steering wheel, particularly when turning at low speed or when the steering is loaded at standstill, the universal joints are replaceable without removing the entire column assembly. Split rack gaiters allow contamination of the rack mechanism that accelerates internal wear and eventually requires complete rack replacement, gaiters should be visually inspected at every service and renewed at the first sign of deterioration, as gaiter replacement is cheap compared to rack replacement.
Two Child Pages
Column & Rack covers the steering rack (MGF and MG TF variants), rack mounting components, rack gaiters, track rod ends, intermediate shaft with universal joints, steering column with adjustability mechanism, EPAS motor and its control unit, ignition lock, and column-mounted stalks and switches. Steering Wheels covers the original-equipment steering wheels fitted across the MGF and MG TF range (including the specific wheels for Trophy 160, 80th Anniversary, LE500, and 85th Anniversary), Momo aftermarket wheels for owners wanting a different feel or appearance, steering wheel bosses and adapter kits, airbag compatibility considerations, and horn push assemblies.