Gearbox input shaft bearing on the way out?

[JonT]

Pls redirect to another thread if I've missed something;t I've spent the morning looking to see if this query might already have been answered on a different thread, but have drawn a blank.

Over the last year, my 306 HDi (168k miles) has developed a low-frequency resonant noise which:

• Is related to engine speed rather than road speed;
  
• Is absent when in neutral, irrespective of revs or whether vehicle moving;
  
• Disappears when I dip the clutch;
  
• Is noticeable in all gears;
  
• Is most apparent at low revs - up to about 1250 rpm;
  
• Is progressively getting worse, suggesting it could be wear-related.
  

It doesn't quite seem to fit the symptoms of a worn clutch release bearing - discussed elsewhere - but a bit of research, specifically http://www.fiatforum.com/punto-ii/158346...newal.html suggests it could be the gearbox input shaft bearing. Grateful for any thoughts; this has been a long time developing but don't want to be driving around with an iminent gearbox failure!

Thanks,

Jon.

[Edited to include correct link to Fiat Forum]

[Poodle]

Sounds like the release bearing to me, what makes you think it's not? Will you be doing the work yourself or taking it to a garage?

[Grant]

I would be very surprised if the input bearing had gone before the release bearing. Have you got any history of the clutch having ever been done? And as poodle says, what make you so confident it isnt the release?

[JonT]

I would be very surprised if the input bearing had gone before the release bearing. Have you got any history of the clutch having ever been done? And as poodle says, what make you so confident it isnt the release?

Hi gents, thanks for your replies. I can't be sure that it isn't the release bearing, but other posters suffering worn release bearings describe the noise occurring either when they depress the clutch pedal or when the engine is idling in neutral. This seems different to my 306, where the noise only occurs when driving. Indeed, if I depress the clutch when driving along, the noise goes away. You'll gather I'm no expert though, so am quite open to advice!

The clutch is original; no work ever done on it as far as I know (I've had the car since 29k).

Due to work pressures (and can't risk having it off the road if I cock it up), I'll prob take it to local (v good) garage. I prefer to let them draw their own conclusions, but to date they haven't been able to pinpoint the fault so would be good to know a bit more before I speak to them again.

[Niall]

I Agree with the guys above. As an educated guess, i would say release bearing but unfortunately its one of them things where its impossible to know 100% without having it all apart. Generally, input shaft bearings dont give up. Release bearings on the other hand can be quite common and for some reason, seem to be more so common on peugeots!

[Toms306]

168k on one clutch? Lol, wouldn't surprise me if it was the release bearing tbh, I've heard/seen a few failing on HDi's, usually at much lower milage.

I've never had any gearbox issues on a HDi though.

[Poodle]

If it's the original clutch it can't have much life in it anyway, i'd be inclined to get that replaced and get the garage to check the condition of the input shaft bearing while they're there. You're right about release bearings normally being noisy in the other direction, if you know what i mean, but it varies - had one in the other day that only made the noise when revved out of gear, bit random...

[JonT]

Guys, many thanks for your replies - much appreciated.

She's certainly done well on the original clutch - though most of the mileage has been long-distance. I'll do as suggested - new clutch & release bearing, and will ask them to check the input shaft bearing at the same time (assume it should be accessible during clutch replacement?).

Is there anything else you think would be sensible to do while this is in bits?

I'll post the findings on here.

Thanks again.