Hi Glyn I have similar issues with my 360S S3, which I built as a new kit and has been on the road a month. I've driven Caterhams before and don't remember the drivetrain rattle and whine but maybe that's selective memory or they had another diff. I plan to find some time to put it back on the stands and check all the propshaft, diff, and driveshaft connections for torque and any play. There is definitely a clunk on occasions when I release the clutch when changing gear on the move. There's also a occasional clunk or rattle when going over bumps which I'm thinking might be the A frame, diff, or play in the driveshafts. I've got the BMW diff which is marked as LSD even though that was an extra which I didn't order. Initially I was really pleased as I'd debated whether to go for it but shied away on cost grounds. Having read lots of comments since about the downsides of the noise and wear/need for rebuilding I'm beginning to wonder if it was such a 'gift'. Would anyone go as far as recommending I push Caterham to replace it with the standard diff that I actually ordered?
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