I have a 2016 Sigma engine with a 5 speed gearbox and BMW diff, so very similar set up to you and I wear earplugs due to the whine around 50mph. Have always assumed its gearbox whine.
Midlife crisis begun....
Thanks Andy nice to know its not only me.
2019 270S 1.6
I wear earplugs because of the exhaust noise. And the diff noise. And the gearbox noise.........
They are definitely normal!
I just think anything noisier than the wife cant be normal
#25 When mine was rear ended a week after I collected it, it went back to Caterham to have the damage sorted. I did a sneaky upgrade at the same time and got them to fit RBTB. When SWMBO went in it next she said its far more noisy than before is that because it went back to Caterham so use it as an upgrade opportunity
I have a 2008 R400D I purchased mid 2020. It had a diff whine from the start. I had a Tracsport LSD fitted towards the end of last year, so I know the unit is functionally OK and set up correctly. It still whines.
I recently did some research on here and found the thread about oils. I'd initially filled the diff with Comma LSD oil. I changed it to the recommended Ford SAE 90. The whine now 'appears' to be in a smaller rev band, but it's still there.
I contacted Steve Perks and he said I could try Red Line Heavy (red) Shock Proof Oil. At around £26/litre and the fact I'd need 2 bottles, I haven't tried it yet, and not sure that I will. I use ear plugs anyway, and putting my foot down removes the whine
Thanks for your comments Dave. Its a case of do I leave it or do I change the diff. If I dont change it I will always wonder if it would have eliminated the noise. The diffs sold by Oakmere are new and not reconditioned..
My 310R with LSD and lightweight flywheel whines. It's done it from new. Could be gearbox though. Who knows? All normal according to Caterham.
Gulf Racing 310R
#28. The diffs fitted by Caterham are new, so yours is only 2 years old and an open diff? Barely run in. Bear in mind that this diff is used by BMW on a range of cars and they do t suffer from whine etc at then they aren't bolted almost solidly to the chassis 6" from your backside!
What's the price of a new open diff? £2k+? Hell of a wager when the odds are it'll be no better; maybe a little different but better? I doubt it.
You seem to be doing what lots of others have tried in the past searching for what doesn't really exist.