IsItAGoodCar
Reliability Guide

Common Problems with the
1970 Austin Maxi

Maxi Series update: rod-operated five-speed gearbox replaces the cable linkage, 1748cc engine introduced, followed by twin-carb 1750 HL and Hydragas suspension in 1978.

What changed for 1970

  • •Factory rod-operated gear linkage fitted, significantly improving shift precision and feel
  • •1748cc E-Series engine option launched, providing 84bhp and relaxed 70mph cruising
  • •Twin-SU carburettor 1750 HL introduced October 1972 with 95bhp and sports instrumentation

Common MOT watch-outs

  • !Corrosion at the rear suspension radius arm mountings and luggage floor pan
  • !Hydragas displacer nitrogen gas loss causing uneven ride height and harsh damping
  • !Oil seal failure behind the clutch causing oil contamination on friction linings
3
Known Issues
1
Serious
2
Moderate
0
Minor

All Known Issues

Front Subframe and Sill Structural Corrosion

SeriousBodywork & Rust

Like its BMC and British Leyland siblings, the Austin Maxi suffers from severe structural corrosion in salt-belt UK road conditions. The steel front subframe that cradles the transverse E-Series engine is prone to rusting from the inside out, particularly in the hollow boxed section between the suspension lower wishbone pivot mounts. Simultaneously, road grime and spray rot the outer sills, the lower A-pillar bases, the rear trailing arm mounts, and the tailgate seal flange. Subframe perforation leads to MOT roadworthiness failure and risks front suspension collapse if left unrepaired.

Est. Repair Cost: £450–£1,400 for structural subframe fabrication, outer sill replacement, and rustproofing
Warning Signs:

Flaking rust, soft metal, and perforations visible on the front subframe between suspension arm mounts, Crumbly outer and inner sills, particularly where the front sill meets the lower A-pillar, Creaking or groaning from the front chassis when traversing uneven road surfaces, Doors dropping or binding in their frames due to loss of body torsional rigidity

What to Inspect:
  • Inspect the front subframe metalwork between the suspension mounting pivots with a torch and probe
  • Check the full length of both sills, jacking points, and rear radius arm mountings for fresh filler or thick underseal
  • Open the rear tailgate and inspect the lower aperture flange and spare wheel well for water and rot
Verified by IsItAGoodCar Research TeamUpdated

Early Cable-Operated Five-Speed Gearbox Vagueness and Linkage Wear

ModerateGearbox & Transmission

Early Austin Maxi 1500 models from 1969 to late 1970 utilized a flexible cable-operated gear selector mechanism that is notorious for imprecise, rubbery shift quality. Over time, the internal selector cables stretch, their outer casings fray, and the plastic quadrant bushes perish, making gear selection extremely difficult and prone to missing slots or selecting reverse inadvertently. In addition, the primary drive oil seal behind the flywheel can harden and leak engine oil into the clutch bellhousing, causing severe clutch slip. British Leyland replaced the cable system with a rigid rod-operated linkage in October 1970, which is the preferred specification.

Est. Repair Cost: £200–£600 for linkage bushing overhaul, rod-change conversion, or gearbox reconditioning
Warning Signs:

Extremely vague, sloppy gear selection with difficulty locating second or reverse gear, Gear lever feels rubbery with excessive free play across all gate positions, Crunching between gears or jumping out of fifth gear on the motorway overrun, Clutch slippage caused by oil leaking past the primary drive oil seal onto the friction plate

What to Inspect:
  • Shift through all five forward gears and reverse both stationary and while driving to check positive engagement
  • Inspect underneath the car to determine whether the original 1969-1970 cable linkage or updated rod linkage is fitted
  • Check for transmission fluid leaks from the bottom of the sump gearbox and listen for bearing whines in fifth gear
Verified by IsItAGoodCar Research TeamUpdated

Hydrolastic and Hydragas Suspension Fluid Leaks and Pressure Loss

ModerateSuspension & Chassis

The Moulton interconnected fluid suspension (Hydrolastic on 1969–1978 models; Hydragas on 1978–1981 models) provides an exceptionally supple ride but degrades as displacer units age. Flexible connecting hoses perish and crack, metal fluid pipework running under the floor corrodes, and displacer internal rubber diaphragms or nitrogen gas spheres slowly lose pressure over decades of use. When pressure drops, the car sags towards the bump stops on one side, destroying ride comfort, causing harsh bottoming-out on road undulations, and severely compromising handling stability. Recharging requires a specialist Churchill-style displacement pump.

Est. Repair Cost: £180–£500 for specialist system pump-up, flexi-pipe replacement, or refurbished displacers
Warning Signs:

Car leaning or sitting noticeably low at one corner or across one entire side, Excessively bouncy, underdamped ride quality or harsh, solid suspension over bumps, Green-tinted fluid weeping from displacer hose unions or underbody interconnecting pipes, Bottoming out over road undulations with reduced ground clearance

What to Inspect:
  • Measure ride height on level ground from wheel centre to wheelarch lip and compare against factory specification
  • Inspect the flexible suspension pipes and displacer canisters under the inner wings for leaks, corrosion, or perishing
  • Ask whether the car has had its suspension professionally recharged with correct fluid and nitrogen pressure
Verified by IsItAGoodCar Research TeamUpdated

Buying Tips for 1970 Austin Maxi

  • 1750 HL and HLS models are the most usable classics, offering brisk performance and plush cabin trim
  • Check that unique rubber-ended bumpers and exterior trim on 1980 Maxi 2 models are intact and undamaged
19691971–1981
Check a 1970 Austin Maxi by Registration