Trani bearing sounds

[nathan.chase]

Hi,

Trying to diagnose what sounds like bad bearings in the trani. The typical grinding, wiring sound of a bad bearing. thinking of buying this car. 130K 5sp, list$1500.

 

Symptoms:

• No noise when clutch pedal is down
  
• noise when in neutral and clutch is out
  
• Lots of noise when accelerating
  
• no noticeable noise when coasting or decelerating (could be covered by motor and street noise though)
  
• some noise when the engine is off and rolling in any gear forward with the clutch down.
  

Possible Diagnosis I've thought of:

• Throwout bearing- shouldn't this only grind when pushing down on the clutch pedal? why would it make so much more noise when accelerating and no noticeable noise when coasting and decelerating.
  
• other internal bearings in trani? - makes noise when any gears are moving, or when the clutch is out and in neutral (trani input shaft is still moving in all of these scenario I think). perhaps a bearing associated with the input shaft.
  

 

History: car had clutch replaced at 100K. Hillstart added at this point.

 

Conclusion: Seems weird to have TO bearing issues 30K after replacement. although TO can cause alot of noise at wierd times when they are shot it shouldn't make noise when rolling in gear and the engine is off, right? Seems most likely another internal bearing but having never worked on trani's I don't know.

 

thanks

NC

[GeneralDisorder]

Transmission input shaft bearing - the rear one. Been there, done that. Find a used tranny (not hard).

 

GD

[nathan.chase]

How much time does it take to replace a trani? How much effort for a backyard mechanic? I did my first timing belt in about 6 hours to give you an idea of how fast I work.

 

thanks

[GeneralDisorder]

You have to get the car up high enough to drop it - I use 6 ton jack stands. The tranny's are pretty heavy so it's best if you can get a transmission jack - I use the harbor frieght $80 one and it works fine. I used to wrestle them in by hand but that's just too much frustration.

 

Wrestleing the tranny out and in again is always a chore - this is why most of us pull engines for clutch jobs rather than mess with that transmission .

 

Only time I remove transmissions is to replace or rebuild one. It's just that much of a pain.

 

I can do them in about 4 hours. But I've done a lot of them.

 

GD