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Hi,

A couple of days ago I was driving the car and misread the gears and ended up downshifting to 1st gear going at about 30kms. The car obviously didnt like it cause it jerked and ever since then there is a rattling noise from under the car. Bell housing?

Update: Local mechanic thinks its from the exhaust.... we'll see when he has a hoist free.

Edited by hzrdus
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https://www.sau.com.au/forums/topic/411917-rattling-suspect-transmission/
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Could be the exhaust hzrdus, it has only been on there for a few hundred kms and a couple of track days so could probably do with a check of all bolt tensions.

The only noises I ever heard was the standard idle rattle and the dash had a rattle but that was fixed under warranty (couple of bits realigned).

If the car is still stock (other than exhaust) I would say its impossible to damage the car by doing a downshift like that.

put it on the hoist, and it sounds like its a cat failure. rattling sound travels throughout the exhaust, my mechanic thinks its the cats (honeycomb has come loose). dont think this will be covered under warranty as it has a willall exhaust system, so know im going to have to find some hi flow cats to replace it as the rattling annoys the fk out of me.

Just make sure you have a good think before changing the cats...

At this stage you should have a good case for having them replaced under warranty, given the only modifications are downstream of the secondary o2 sensors. Northside certainly indicated that the exhaust modification would not affect drivetrain warranty.

Replace the cats and you will probably need to remove an engine light for the secondary o2 sensors which will void the warranty.

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Could be the honeycomb in the cat I have a 2011 and mine does the same thing it's getting fixed through warranty aswell as my brakes as rotors... Dealer offered aftermarket brakes and rotors but not sure which ones I should say I want

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