HK-HG Monaro / GTS

1968-1971 / Coupe / Australia

All HK-HG Monaro / GTS problems All workshop issues

Critical Pillarless Coupe, Specific Issues

Body Flex (Coupe)

Symptoms

Doors don't close properly on uneven ground. Dashboard cracks. Windscreen seals pop out. Creaking and flexing noises over rough roads.

Cause

The pillarless coupe body is inherently less rigid than the sedan because it lacks B-pillars. If the structural elements (sills, A-pillars, floor pans) have been weakened by rust, the body flexes more than designed. Even a solid coupe body is less rigid than the sedan.

Fix

Ensure all structural elements are sound, any rust in the sills, A-pillars, or floor pans must be repaired properly.

Some owners fit subframe connectors or chassis stiffening kits to reduce flex.

For race cars, a full roll cage provides the necessary rigidity.

Know something we don't?

Owned a Holden HK-HG Monaro / GTS? Share your experience with this issue. What worked, what didn't, costs, tips. Help the community.

Submit an update

// More HK-HG Monaro / GTS problems

Other known issues

Common Pillarless Coupe, Specific Issues

Frameless Window Seal and Alignment

Wind noise at speed, water leaks in rain, windows don't seal against the roofline rubber, windows rattle when closed.

Critical Engine, Chevrolet V8 (327ci / 350ci)

Intake Manifold Gasket Leaks

Coolant leak at the front or rear of the intake manifold. Coolant may drip externally or, worse, leak internally into the engine oil. May also cause a vacuum leak, resulting in rough idle and poor fuel economy.

Common Engine, Chevrolet V8 (327ci / 350ci)

Rochester Quadrajet Carburettor Issues

Hesitation on acceleration (bog), flooding, fuel smell, hard starting when hot, black smoke, erratic idle.

Critical Engine, Chevrolet V8 (327ci / 350ci)

Overheating Under Load

Temperature gauge climbs on highway drives, particularly towing or climbing hills. May push coolant out the overflow. Engine pings (detonation) under load.

Common Engine, Chevrolet V8 (327ci / 350ci)

Hydraulic Lifter Noise

Ticking or clattering from the top of the engine that varies with RPM. May be audible at idle and disappear at higher RPM, or vice versa.

Common Engine, Holden Six (186ci) and V8 (253ci)

Oil Leaks, Rear Main Seal

Oil drips from the bellhousing area. Oil accumulates on the underside of the engine and transmission.

View all 18 HK-HG Monaro / GTS problems