Clutch Problems....

the most likely cause is the booster leaking vacuum through the front seal, behind the master cylinder. the booster overhaul kit is relatively inexpensive but i sugest that you have a mechanic over the booster.
regards mars

a problem i came accros on our gq was the throw out fork was cracked and sometiomes wouldnt throw all the way.
i thought it was the clutch going so i pulled the old clutch out and found the problem.
cheers.

Kero,

All the above suugestions have merit. Another one to consider is that the vehicle has done a high mileage and this is starting to show in clutch performance.

Modern clutches consist of the back face of the flywheel, the spinner plate also known as the centre plate) and the pressure plate. The pressure plate applies pressure to the spinner plate by a conical shaped diaphrgam made of spring steel. It's a very shallow cone but a cone nevertheless. When you put your foot on the clutch pedal, you apply pressure to this diaphragm "spring", the initial reaction on your foot is one of pressure from the resistance of the spring diaphragm, then as the diaphragm "goes over centre" i.e collapses the diaphragm or turns it inside out, the spring actually helps the clutch to release and the release pressure at your foot becaomes less. I can't think of a suitable anaolgy to describe this.

When a pressure has a load of miles on it and it has experienced a lot of heat, this spring starts to lose it's temper (i.e tension), and the consequent flip flop, inside out collapsing of the diaphragm becomes almost non-existent. It then becomes difficult to press the clutch down (and hold it down) because this "self servo assistance" is no longer there.

I would suggest a new pressure plate at least. I renewed my GQ clutch at 200,00 kms when it was getting a bit hard to press. When the clutch was inspected the rivets holding the clutch friction linings on the were just about to touch the rear face of the flywheel. So it was time anyway. When it was all rebult with a new pressure plate & thrust bearing it was a completely different truck to drive. A pleasure. You don't realise how bad it was until you put a new one in 'cos you get used to it over time. Same applies to brakes.

Bilbo