[ricnor]

Thanks for the quick responses, the pedal is firm not spongy but as I said very occassionally it has gone to the floor, maybe 3 times in a year.
Over here we have to have a test on our vehicles every 12 months and part of the test is to check the brake efficiency on rollers hooked up to gauges. whenever the truck has been tested it passes without issue, they first check that the brakes are not binding by running the front wheels on the rollers without pressing the pedal, if everything is fine they then do one wheel at a time and the readings are fed into a computer, after doing the two fronts individually they then reset the rollers and do a test on both the wheels at the sametime to make sure that one side is not better than the other.
This is then repeated on the rear wheels in the same way but now twice over, one lot for the foot brake and then all over again for the parking brake only.
I will check the rear brake shoes for wear just to see.
The power steering works a treat without hesitation and is nice and light, plus similar to an ordinary vacuum brake booster if I put my foot on the brake pedal and then start the engine the pedal goes down a fraction so to me it would appear that the system is working. (hope this is correct).
I am concerned with the brake going to the floor so think I will get a new master cylinder as a start and see if it makes any difference to the overall braking efficiency of the truck.
As I have said I have never been totally happy with the way the truck brakes but can't believe it is something that can't be cured, it's a big heavy rig not to be able to stamp on the brakes and know you are going to stop