maxz32

Sometimes my 1996 Maxima (manual transmission) shudders when I take off from a stop. This seems to only happen when the car is cold and hasn't really warmed up. Does this symptom have a usual cause?

Thanks in advance.

Daniel B. Martin

You are describing Clutch Chatter.

Chatter is a rapid slip-grab-slip-grab phenomenon. The clutch engagement is "jerky" instead of smooth. Clutch chatter is felt more than heard. It occurs only while the clutch is engaging, and is most noticeable when starting from rest. As soon as your foot is off the clutch pedal the chatter stops.

Clutch chatter may be caused by, or aggravated by,
- oil or dirt on the friction surface (leaking rear main engine oil seal)
- glazed friction surface (excessive heat resulting from abusive driving practices)
- pressure plate diaphragm spring misaligned
- loose or broken engine mounts

If the chatter is not severe the best thing to do is "just live with it."

maxz32

Thanks for the fast reply Daniel. The entire engine seems to shake when I try to start from a stop after just starting the car. This would lead me to believe that from your list, the loose or broken engine mounts could be a cause or agrivation of the problem. So I guess after the clutch is warmed up it allows for more slip and thats why this doesn't happen after I drive for a while?

blizz20oma

iTrader: (1)

Is there anything necessarily bad about the clutch if it chatters? It seems at random it will happen to me...it's mostly something I can feel in the clutch pedal ,but it can be heard if listened for. Does the common maxi clutch chatter happen in motion shifting up through gears? If I give a blip too much gas when the clutch is deep enough shifting, I notice it as well as when taking off at times.

I do the 5th-gear-low-RPM-floor-it test, and see no slippage whatsoever. To me, it seems just an annoyance (hopefully one that I can eliminate when I have some extra money in the near future).

Daniel B. Martin

Chatter is not a symptom of impending failure. It is an annoyance. It may be a sign of a leaky rear main engine seal. Keep track of oil usage and watch for under-car drips.

Neptune97

I too suffer from clutch chatter when the engine is cold. What I've noticed is that I also get chatter when I've been travelling a long distance without having to change gear (ie greater than 30 mins).

From this I have deduced that my clutch chatter is probably related to either a glazed friction plate or some kind of oil between either the flywheel and the friction plate or the friction plate and the pressure plate (as opposed to an engine mount problem). Repeated engagement of the clutch somehow fixes the problem (whether it changes the properties of the glazed surface or somehow removes oil from one of the plates)...but its not necessarily related to whether the engine itself is cold or not. Rather whether the clutch has been engaged recently...

Although I could be completely wrong...I am having a new clutch put in before the winter, and I'll ask my mechanic if he saw anything out of the ordinary when he changes it...might even ask to look at the removed clutch.