Slowly and if you are good you can change gears without using the clutch. Takes a little practice and a good ear or feel for when the engie is running at the speed to change without the clutch.
Every time you engage the clutch, the clutch disengages from the transmission/engine. Which in term engine revs up, until you disengage the clutch.
If you mean out of specification, abnormal clutch wear, poor performance when the clutch engages, stuttering when changing gears, engine running higher rpm and having less power and forward movement.
I think I know what you are talking about, when you let out your clutch the car shudders as it engages. This isn't normal, and is probably due to glazing of the clutch disk, this will form a varnish on the disk and when you engage the clutch it will grab and release the flywheel quickly before it engages completely giving you that shudder. The reason it doesn't do it all the time when starting from a stop is because your engine rpm is a bit higher than usual and it has a smoother transition, the quicker engine rpm prevents the grab and release, it should almost never happen when you are moving because when the rpm of the engine and transmission are closely matched the catch will be instant, no need to let the clutch out slowly when you are already moving. You can sometimes remove the varnish causing you trouble by bringing your rpm's up a little higher than usual and letting the clutch out very slowly, this can burn the varnish off and leave a fresh surface, it doesn't always work, but I have had good luck with it.
I would first check the master cylinder, and slave cylinder. Not knowing anything about the auto, most use hydraulics to release and engage the clutch. A clutch disc will tend to slip when in higher gears when it starts showing signings of wear. Most car companies use dot 3 brake fluid in their clutch systems.
by changing the clutch springs.. weak/aged springs = low rpm/slow take off, stiffer springs= higher rpm/ faster take off. 1. drain oil and remove right hand side engine cover. 2. remove clutch bowl. (remove circlip & slide bowl off) 3. clutch pads are now exposed, the clutch springs hold these pads together. 4. remove and replace these springs.
You can tell by how much higher the clutch pedal is to the brake pedal. when new pedals are at the same height.
The clutch will slip in higher gears first. Cruise about 40 mph in 4th gear and step on it, if the rpm's go up more then the speed your clutch is going
If you clutch and it either goes all the way in with no pressure there is a leak in your slave cylinder or the higher you have to clutch means your clutch is sliping and has to be replaced. If your doing a lot of power shifting i would suggest you get a racing clutch instead.
Gearboxes on trucks are generally not synchromesh. It means there is no mechanism to automatically adjust the speed of the engine and the gearbox to match. Therefore if we would simply change gears like in the modern passenger car equipped with the synchromesh gearbox by depressing the clutch and shifting the gear up or down before releasing the clutch the different speeds of the engine and the gearbox would cause the grinding. To avoid this change requires process called double clutch. It goes like this: 1. Depress the clutch, 2. Shift the gear into neutral, 3. Release the clutch, 4. If shifting down depress the accelerator to rev up the engine so the rpm's of the engine are slightly higher than the gearbox and release it; if shifting down depressing the accelerator may not be necessary if the whole process is done quickly enough, 5. Depress the clutch again - that's why it is called double clutch, 6. Shift the gearbox into next gear (up or down). At this stage the rpm's of the engine will be slightly higher than the gearbox and the engine will be slowing down at some point the speed of the engine and the gearbox will match and the gear will go in without grinding. This needs to be done with the feel and with the bit of practice it becomes automatic. The amount the engine needs to be speeded up will depend on the conditions for example if changing gears when going up the hill.
By vibrating quickly, the wave would have a high frequency.
Try adjusting the clutch. Never downshift to slow down, press the clutch and use the brake to slow down it will save your engine and clutch. Downshift to pass or to rapidly speed up but be sure to have the revs up higher than when you were in the higher gear.
diaphragam clutch is small in size as compare to spring clutch and it transmits more torque as diaphragm exerts more force as copare to springs...... therefore it is advantageous to use diaphragm clutch intead of spring clutch... more compact means of storing energy. thus compact design results in smaller clutch housing......... less affected by centrifugal force..can withstand higher rotational speeds... diaphragm acts as both clamping spring and release levers..therefore many extra parts like struts, eye bolts, levers etc can be eliminated....