Whining diff?

[Griff2be]

Whilst sprinting down the runway at Duxford on Saturday I noticed a peculiar noise coming from my car. When I hit the brakes at 130-140mph I got a loud whining noise which lowered in pitch as the car's speed scrubbed off. The whining was almost like a whistle (sounded a bit like being dive-bombed!). The first time I thought it was the Ferrari 348 behind me, but then I realised how far behind me he was

Next time round was quicker and again, as soon as I started deccelerating, the whine started. I messed about both on and off the brakes, in gear or clutch dipped. The noise only varied with the road speed and only on decceleration. I assume its the diff?

The weird thing is I cannot get the car to replicate the noise at lower speeds. 110mph and braking it won't do it. Yet when it started the noise at 135mph it kept making the noise right down to 30mph.

Very odd. Anyone have any ideas?

[zippy500]

Curious, mine does that, although whilst slowing down from 90 odd mph. Its done it 3 times now. Never seems to do it when slowing down from slower speeds. It dosent sound like the pads or anything and I have checked them all over and they look fine. Very strange.

[andyvg]

Mine did that at Duxford as well - just as you hit the braking area the car makes a weird transmission type noise, I went up in a 3000M as well which did it as did several other people I spoke to.

I expect it was more due to the road surface rather than the car - probably caused by winding the car right up to the limit and then braking harder than you normally would on the road - my car was fine on the drive home.

Just had Exactly TVR check the car out and MOT it and they didn't mention anything so I'm not worrying about it!

[SMB]

Limited Slip Differentials often make some noise on the overrun, given you don't normally get to those speeds, that's probably the only reason you haven't heard it before. Wouldn't worry about it.

>> Edited by SMB on Tuesday 13th August 09:02

[Russlarc]

Id put the noise down to the road surface at the end of the runway. Tended to cause a resonance. Any civil engineers amongst us might tell us why.

My diff whines on the overun and was no worse at 130.

[griff2be]

Glad to hear I'm not alone in this. Still seems odd though!

[simpo one]

The first sign that the diff on my old Griff was in trouble was a deep whining noise from the back when I took my foot off the gas. And as someone said 'Cars are not like us, they don't repair themselves, they only get worse....'