Hi guys,
I know that not using the clutch is usual practice if you are using a Roadranger.
Is there any reason to not use it on a syncromesh gearbox, like on the Scania P94 that I usually drive.
Cheers,
Aux1.
You dont need if you can (without much Noice) 
Synchromesh gearbox - use the clutch. Constant mesh gearbox - use the clutch. Crash gearbox - use the clutch. The synchromesh cones, the dog clutches, the gears, the selectors and the splines on the shafts are all designed only to release and to take up the torque of themselves freewheeling, not trying to deal with the effect of 44 tonnes suddenly being imposed on them parts. This is what the springs in the clutch plate are there for. They (the cones etc) are not designed to mate the speed of the rotating parts under these conditions.
While it is possible to time a non synchro box change absolutely perfectly without using the clutch, there will be a substantial proportion of changes that are just a little bit out, they may be out just enough to cause accumulating damage, but not enough to wipe the grin off the face of the willy-waving driver.
Edit: in brackets to clarify
cav551:
Synchromesh gearbox - use the clutch. Constant mesh gearbox - use the clutch. Crash gearbox - use the clutch. The synchromesh cones, the dog clutches, the gears, the selectors and the splines on the shafts are all designed only to release and to take up the torque of themselves freewheeling, not trying to deal with the effect of 44 tonnes suddenly being imposed on them parts. This is what the springs in the clutch plate are there for. They are not designed to mate the speed of the rotating parts under these conditions.
While it is possible to time a non synchro box change absolutely perfectly without using the clutch, there will be a substantial proportion of changes that are just a little bit out, they may be out just enough to cause accumulating damage, but not enough to wipe the grin off the face of the willy-waving driver.
I was generally driving without Clutch and never had a Fault. Not on Clutch,not on Gearbox,Axle or anywhere else.
I had 3 Blow out on Trailers. Everytime on Middle Axle
I couldnt twice not Start as Battery flat
On a Eaton Twin Split was a Rubber Ring on Gear Stick Switch worn out
on a 320 DAF blow a Turbo
think that was it ruffly. Did quiet a few Millions on the Tacho and went well most of the Time. Just once i had a Daf for a few Week which used 10 Liter Oil a week,but handed them quick back.
And,Yes. Half of the Driver running long Distance were driving without useing Clutch. The one learned it quick,the other needed longer to get it.