Grande Punto Car making a weird sound in 3rd gear

[bethpunto1]

Hi everyone,

I’ve just come across an issue with my Fiat Grande Punto yesterday. When I’m in 3rd gear at around 20mph there’s a horrible screeching sort of noise. It doesn’t happen in any other gear just 3rd gear. I’ve been suggested that it could be the synchro but I’m no good with cars so I wanted some more info on what it could be. I’m taking it to the garage Tuesday for other reasons but I don’t want to drive it in case there’s a risk of me breaking down somewhere. I hope someone can help!

 

[varesecrazy]

Hi.

Sounds like the gearbox..

Does it get louder if accellerating?

If you press the cluth pedal down
Does it go quiet??

Charlie

 

[bethpunto1]

Hi Charlie,

It gets slightly louder if I accelerate and goes away if I take my foot off of the accelerator.

Beth

 

[SRafferty]

Might be a bearing in the gearbox? The first thing I'd do is have someone check your gearbox oil.

 

[Bernievarian]

Since gearbox pinions aren't straight cut (teeth not parallel to the shaft), there is a certain axial force that is applied on the pinions and this force have to be absorbed by the bearings.
The more the torque, the more the force, the more the (potential) noise...
In reverse action, the force changes to the opposite direction so as the (potentially bad) bearing is released from axial stress, the noise disappears...

Well, at least that corresponds to the given symptoms...

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

 

[bethpunto1]

Someone I know also suggested a bearing. I take it in tomorrow so fingers crossed all goes well. Thank you all for the help. I’ll let you know what the verdict is tomorrow

 

[bethpunto1]

So here’s the update. While I was driving to the garage the car didn’t seem to make the screeching/squealing noise at all. However, I did mention the noise to the mechanic and he said he’d take a look while he was fixing the things I went for.
When I went to pick it up he said he’d taken it for a run and said he couldn’t hear a noise so couldn’t figure out what it was. So now I’m just going to have to wait until the noise starts again and hopefully they can find out what it is.