Electric fuel pump in tank failed not long after I bought car (am told some cars are running their 3rd or 4th pump). (I often worry that an electric motor is running inside 68 liters of petrol, but I guess Holden know what they were doing?) If this happens to you in the middle of nowhere, thump the bottom of the tank hard with your fist, this should get the pump going... till the next time you stop.
Speedo sensor on Automatic transmission box failed at about 270,000.
Harmonic Balancer failed at the 280,000 mark. Symptom is clunking noise coming from it while idling, but noise goes away when off idle. Cost about $300 to replace.
Replaced all 4 shocks as the car used to wallow on the highway. Rears are easy, but fronts more difficult as they are inside the struts. (it is a 15 year old car after all)
Short Coolant hose at rear of motor near thermostat burst (this one is hard to get at).
Replaced Timing chain and tensioner at 300,000 as the rattling was driving me nuts. Dramatic improvement afterwards, restored power and better fuel economy. Any V6 with over 200,000 will probably need this replaced. All parts, including replacement chain and gears, tensioner, gaskets, oil, etc will cost about $250.
Like all the other reviews say, the door trims fall off, and plastic parts break as they get old and brittle. Always keep a tube of glue in the glovebox handy.
Hood lining drops (mines a stationwagon). The velcro pads inside the roof no longer hold, Araldite fixes this.
Usual stuff replaced...plugs, leads, filters, fluids, exhaust, brake pads etc.
Paint goes off (especially lighter metalic colours) Had the bonnet and roof resprayed for $800.
Upper panhard rod bush was very worn. Mid corner the rear would suddenly change direction! Very dangerous. Replaced bush when I found out it was the culprit.
Auto transmission sump leaks a lot, replaced gasket and filter.
Engine leaks from sump, rear mains, front crank seal, rocker covers and rear of inlet manifold. Replaced front crank seal when did timing chain. Tightened sump bolts (You can't get to half of them due to the crossmember. To replace the sump gasket you have to remove the engine!) Tighten rocker covers and inlet manifold nuts, makes a difference.
Power steer hoses leak. Replace them.
Auto trans fluid leaks where they go into the radiator for cooling, tighten the clamps.
The radiator fan fuse blew. Then the fan doesn't work and your car overheats at idle. This is because the wire going to the fuse is too thin, causing resistance and heat. Put in a inline fuse and thicker wire. The VN's are notorious for cooling system problems, use good coolant or it will corrode in no time. Don't use the cheap green coloured cordial stuff.
Ventilation fan only works on one speed (3rd in my case). Replace the resistor for it located near the wiper motor.
Some surface rust at bottom of door sills. Spray lots of fish oil on these and inside the doors, tailgate (or boot), etc.
The serpentine belt tensioner bearing fails or just gets wobbly (sorry for the untechnical word). $29 for new one, comes with new pulley. Apparently this is a common fault.