Change down to second

[lucozade]

My 3R (6 speed box) suffers from a loud noise when I change down to second, anybody else getting this?

[DanH]

Coming from where?

[lucozade]

sounds like the gearbox, the noise isn't apparent until the clutch is lifted.

[DanH]

Only when changing to 2nd from certain gears, or from any gear?

[lucozade]

From any gear down to second resulting in revs higher than 3000.

[hunttheshunt]

Isn't this the same noise that we discussed before on a different thread. Is it when the car is quite cold. It certainly sounds like it could be.

I think the consensus last time was that a few people get it, nothing has broken or fallen off yet, so one of those things.

[m12_nathan]

What type of noise?

[DanH]

Does it still make the sound if you rev match on the downchange (heal & toe etc)?

Its definitely only in second?

[lucozade]

only in second and every time I change down from a higher gear resulting in high revs. Well not really high about 4000rpm and above.

The noise sounds mechanical, like something is grinding.

[jaz34]

Same as me. I posted about this back in June I think. I had the car in for it's first service and the engineer noted this but aparently it is nothing to worry about.

I was in the habit of changing from 4th down to second and it is very noticable. I still got it from 3rd to 2nd. Check my thread below....

www.pistonheads.com/gassing/topic.asp?f=26&h=&t=108253

Jaz34

>> Edited by jaz34 on Wednesday 12th January 12:41

[DanH]

What about when you rev match on the downchange though? Is it when there is a rev mismatch on engaging the clutch as things get back up to speed?

[lucozade]

DanH said:

What about when you rev match on the downchange though? Is it when there is a rev mismatch on engaging the clutch as things get back up to speed?

Could well be DanH not thought of that. I shall check.

[Marlon]

There is, apparently, a known issue with the gearbox (so says my dealer). You need to blip the throttle to raise the engine revs to match the lower gear before engaging; if you can't heal-and-toe (bloody difficult with the standard brake setup) then brake early, off the brake and blip before you raise the clutch. Bloody annoying. Didn't notice it on the M400 but I've got used to breaking early or changing down late (<2,000 RPM) so it doesn't happen.

I heard on the vine that Leven may be working on some "better" after-market pedals (adjustable?) so that heal-and-toe will be easier.

[DanH]

Marlon said:

There is, apparently, a known issue with the gearbox (so says my dealer). You need to blip the throttle to raise the engine revs to match the lower gear before engaging; if you can't heal-and-toe (bloody difficult with the standard brake setup) then brake early, off the brake and blip before you raise the clutch. Bloody annoying. Didn't notice it on the M400 but I've got used to breaking early or changing down late (<2,000 RPM) so it doesn't happen. I heard on the vine that Leven may be working on some "better" after-market pedals (adjustable?) so that heal-and-toe will be easier.

Hmm what changes were made to the pedal. It just looks like it was bent a bit!

[m12_nathan]

yep - acc pedal bent towards the brake pedal

[DanH]

So does everyone get this? Not heard of this issue before and not noticed, but I heal and toe.

Will have to have a test. Doesn't make much sense though.

[Marlon]

MICKNALL!
JOUST!

Enlighten us!

[joust]

Sorry. No idea what you are on about (bugger me you've stumped me). Not had that one, although I do remember some discussion about it as above.

Although in general H&T on downchanges is good for any car. I never had a problem with the original pedal layout (look at any of my track videos and you'll see me doing it on each downchange), but I have to say the M400's seem ideally placed (and they ain't bent )

J

[BrianJ]

Yep - graunchig noise if you change down to 2nd, sometimes third at unmatched revs - tells you you've got it wrong!

Brian J

[mikes_3r]

I wonder if it's the same noise we tried to sort through in my car.

It's an intermittent whinning rattling sort of sound usually under decelleration at low speeds and revs (typically no brakes).

www.pistonheads.com/gassing/topic.asp?h=0&f=26&t=126758

Greg Robb, my installer in the states, located the noise in the transmission using a rolling dyno. A subsequent tear down revealed no wear marks, no filings, nothing to indicate a problem. The noise is still present even after the "rebuild" though.

-- Mike