Just a couple quick T5 questions.....trying to learn

1. Is clutch chatter always caused by glazing or could a worn pilot bushing or input shaft bearing cause it? I am wondering more about the bearing as my pilot bushing is new. What about the bearing retainer. What would the effect be if that was worn?

2. Is bearing noise from the tranny normal (i think it is bearing noise) to some degree? I hear a gentle grrrrrr whenever you let the clutch out. Or is this a sign of bearing wear and needing a rebuild (new bearings)?

3. Is there supposed to be some play in the tranny gears that could lead to bucking or is that something wearing in there too (bearings)? Depending on the circumstances, I get bucking and I can hear it making a bit of a racket in the tranny as it takes up that play in the gears forward then back repeatedly.

Any knowledge you could pass on would be greatly appreciated.

 

same prob here.i would say our trannys are wooped but i was told mines has 70k on it. . probraly has more ..theres a surprise a unhonest seller nah never....lol.. and my clutch throw out and piloit are all new so its not them.. i also here the same noises when i let the clutch out in nuetral.ggrrrrrr faintly.

 

You'll know if your bearings are going because the trans will whine in some or all gears.

Chattering of the clutch can be caused by a flywheel that's grooved or worn unevenly. Just think about how a brake disc looks when it gets grooved. Usualy you can get the flywheel machined to get it flat again.

 

in this particular case it was machined. looked beautiful. I have heard some people say that if not machined enough, the hot spots wil still remain. Not sure if that could be the problem???

 

If the flywheel was recently machined it is probably something else I would say.

 

Let's take these questions one at a time, shall we.
A worn pilot bushing could cause this, yes. The input shaft bearing could cause this, but that pretty uncommon. On the other hand, a worn input shaft bearing retainer definatly can cause clutch chatter. A worn bearing retainer allows the throwout bearing to wobble on the shaft, causeing chatter. Also, improperly machined flywheels, as well as broken dirphram springs can cause clutch chatter.

Yes, this is normal. Manuals use constant mesh helical cut gears. They make noise. If you have an aftermarket shifter or a poly trans mount, the noise can be amplified and make the tranny sound even louder. This is also normal, no worries there.

Bucking is caused by the clutch and pressure plate assembly, there is nothing in the transmission itself that causes bucking. The clutch disc has a series of radial mounted springs that connect the clutch face to the clutch splines. When they are quickly loaded up then unloaded, they start to spring back and forth, causing bucking. There are also a set of steel straps on the pressure plate that connect the face of the plate to the body, these do the same thing as the springs and can cause the same bucking.

Both the springs and the straps serve to make clutch opperation smooth and predictable. Without them, getting the car rolling from a stop without stalling the car or spinning the tires is nearly impossible. A true race clutch is like that, and almost inpossible to drive on the street.

 

Wow, thanks fisherbody for the info Now I have to somehow figure out the cause of this chatter. SOmetimes it is so bad that the exhaust bangs against the floor when trying to get into 1st . Always some chatter on downshifting too. Here is the scoop as to what's done and not:

- new clutch, pressure plate, release bearing and pilot bushing
- flywheel machined
- original bearing retainer, fork and ballstud but bearing seemed to fit fairly nice and fork springs were tight in the bearing groove
- there was a wee bit of side-to-side play in the input shaft with the tranny out, not sure what is normal and what isn't though.
- first 3 to 4 weeks after clutch change beautiful smooth engaging and absolutely no chatter.

Any suggestions as to what I should target? Could this chatter do damage if left for a while?

 

"Without them, getting the car rolling from a stop without stalling the car or spinning the tires is nearly impossible."

thats my problim as well i have to ride the hell out of the clutch in order to not spin or make it start bucking. i have a after market performance clutch but i wouldnt think its the type to make it do that.

"Bucking is caused by the clutch and pressure plate assembly, there is nothing in the transmission itself that causes bucking"

what if the tranny has gear slop?

''SOmetimes it is so bad that the exhaust bangs against the floor when trying to get into 1st''

that might be a bad mount too.i would imagine that they would only make matters worse.

 

Actually, I forgot to mention, the mount was done at that time too. The car has not been driven hard since the change so I am thinking it is likely ok (and it is only a 2.8) but I suppose I should peek anyway just out of curiosity.

"what if the tranny has gear slop?"

My apologies, that is what I meant to say that there is slop or space in the gears and then the bucking makes it bounce back and forth between that sloppy space (you can hear a bit of a racket in the tranny when it does that too). Now is there suppoosed to be some slop??