Crankshaft Bearing...Help!

Mack · Jun 8th, 2004, 10:29 PM

I know that there have been several posts regarding this question lately (inlcuding those of mine) but I have a more detailed question about it now. I do not know exactly how long the "knocking" vibration has occurred, but it doesn't happen every time I drive.

1) Could a "slightly" damaged bearing create a knock that comes and goes? (I realize that it still needs immediate attention, I am not driving my Sentra at the moment, either.) Or would a bad bearing create a constant knock?

Just to provide more details, the knock is a vibration that is noticable through the floorboard and is audible (dull and quiet, not a "click" from CV Joints). It feels as if it originates under the engine and occurs while driving straight, especially at higher speeds (it vibrates faster at higher speeds, too) and while turning. It can occur when I take a turn in neutral (clutch pressed) as well as when the throttle is applied. I'm trying to completely rule out what isn't causing the problem (CV Joints, suspension, etc) because getting the crankshaft bearing replaced will be over $1000 at a shop.

2) Could the manual transmission be to blame? The stick doesn't jump or bounce irregularly.

Thanks for any advice.

Mack · Jun 9th, 2004, 07:13 PM

Can someone lend any hints?

I really just wanted to know if a bad crankshaft bearing could make a vibration that is intermittent. My vibration/knocking doesn't occur all the time, so I just wondered if that would be a key towards determining what the problem is. Wheel bearings and the transmission could also cause a problem like this, I guess, so I'd like to isolate the effects.