Why does my diff bang and clatter?

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Andy Mac
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Why does my diff bang and clatter?
And can I stop it ? Can it be adjusted to give clearance? It's LSD. Over bumps It does sound like it's knocking the chassis. Also it whine's a lot on overrun. I know this is a thing we have to accept, but can I sound proof to reduce at all? Thanks.
Tazio
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First thing, 'sounds like banging on the chassis', check all the fixing bolts as they do come loose over time, and I've known the bolts to break.

As for the whining, there are loads of threads re different types of LSDs making loads of noises, so you'll have to add what car you have and what diff is fitted, Ford or BMW to help answer your questions.

Andy Mac
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I believe it's a BMW LSD.

Andy Mac

Dan R
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You, as I have, will now discover the phrase TADTS Rofl

R500sv

'Bravery is being the only one who knows you are scared' 

ScottR400D
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Which engine, bhp, how many miles, how old?
 

Is the diff bolted in properly?

aerobod
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The bottom two bolts where the BMW diff mounts to the carrier can work loose and drop out, (I upped the torque on mine to 110Nm, added blue Loctite and kept the Schnorr washers in place and have since had no problems). Also, if you have an old style carrier that mounts at the top to the diff using two of the cover bolts instead of a long bolt through the top of the cover, the cover bolts can hit the deDion tube when the car is corned hard (there was an upgraded cover available in 2014 or so to fix that problem).

James

Andy Mac
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That's good guys thanks. I think I need to get the car up and do some inspecting. What about some sound proofing for the whining? Or am I being a bit anal?

Andy Mac

Benton
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What about some sound proofing for the whining? Or am I being a bit anal?

On the basis the overall noise level whilst driving a Caterham is already high (mechanical, exhaust, wind etc.) anyway if you don't already wear them then earplugs or headphones are recommended if you're driving for any length of time.

aerobod
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With my BMW diff, the only noticeable whining is on the overrun in 4th gear (I have the 6-spd transmission), but no other whining above the exhaust note in other circumstances. I do run 75w140 oil that seems to help reduce diff noise, especially when the oil gets over 100°C, though.

James

GulfSeven
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With an R it's only the diff housing that's BMW - it's a Titan LSD inside on the current cars which is a different beast all together. I think they all whine. Mine certainly does.

Tim.

Gulf Racing 310R

ScottR400D
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The Titan is capable of making all sorts of noises, especially when it's on its way out. 

It's hard to give clear advice not knowing anything other than 'I believe it's a BMW' though.