Gearbox failure

[gruffalo]

Well I was on a trackday yesterday at Snetterton and lost drive in all gears except 4th. Box makes metalic clattering noise in neutral and simply awfull noises when trying to select any gear other than 4th.

What has broken do people think, it is clearly a major failure inside the box but what?

[MoonMonkey]

Not good news!

I think 4th on the T5 is a direct 1:1 ratio so the input shaft will be connected directly to the main shaft when fourth is selected. All other gears will use the lay shaft to connect drive from the input shaft to the main shaft.

Giving the symptoms I would think the issue is something to do with the lay shaft, or the drive to it from the input shaft.

[gruffalo]

Agreed, this does sound like what has happened.

In the T5 is the layshaft driven directly from the input shaft via a gear set? If so it sound like that has let go, the good news is it did not go with a bang just lost drive and started making metalic clattering.

[Englishman]

gruffalo said:

The good news is it did not go with a bang just lost drive and started making metalic clattering.

Or locked solid as I had recently in a Sag (same gearbox) on a motorway!

[ukkid35]

Is the T5WC used in the Cerb the same as in other TVRs or is the gearset model specific?

[MoonMonkey]

This is an exploded view of the T5WC. The input shaft 65 has a helical drive gear that drives the layshaft 116



Its possible that this has stripped the teeth off one or both of the shafts

If this has happened it will mean a new gear set which I think can be circa £1,000, plus the bearings, synchro rings etc.

I did see this guy selling "new" gear sets for £250 plus vat. May be worth a call.

http://www.v8tuner.co.uk/product.php?id=886

Edited by MoonMonkey on Sunday 17th November 13:35

Edited by MoonMonkey on Sunday 17th November 13:41

Edited by MoonMonkey on Sunday 17th November 13:42

[gruffalo]

Thanks for that very informative, gearbox has only been in the car about 10 months after a rebuild, I will see where I get to with a warranty claim.

I paid for the motorsport upgrades to be done with the rebuild as I do quite a few track days, original standard box lasted 13 years, uprated one 10 months.

Bugger.

[MoonMonkey]

Hopefully the warranty will cover it

Do you know what gear set you have in it?

I saw these guys doing heavy duty gear sets for T5's

http://www.gearboxman.co.uk/infot5.html

[gruffalo]

MoonMonkey said:

Hopefully the warranty will cover it

Do you know what gear set you have in it?

I saw these guys doing heavy duty gear sets for T5's

http://www.gearboxman.co.uk/infot5.html

That would be the one then.

[MoonMonkey]

Oops!

[gruffalo]

MoonMonkey said:

Oops!

Yep.

[gruffalo]

Actually not oops, I have to correct this post as after checking where the gearbox was sent to last time it was not the supplier of those gearsets.

[grahamn]

10 months, you're lucky...mine lasted 6 weeks.

[Boatbuoy]

grahamn said:

10 months, you're lucky...mine lasted 6 weeks.

Yer, but you're mad, madder than Martin, but only just!

[Dave_M]

I lost 3rd on a runway recently, and a shaft (lay I think) was bent too. It's been rebuilt and should arrive back this week I think.

Edited by Dave_M on Tuesday 19th November 19:48

[gruffalo]

I had extra bracing put in mine when rebuilt last time to stop this happening, oh well we will see what is wrong and how much has been munched up.

Has anyone tried the greasets from gearbox man, if so any issues?

[QBee]

"Exploded view" on the picture sounds a bit prophetic..........

[Dave_M]

QBee said:

"Exploded view" on the picture sounds a bit prophetic..........

[gruffalo]

Dave_M said:

QBee said:

"Exploded view" on the picture sounds a bit prophetic..........

Hopefully not, no big bang when it let go.

https://vimeo.com/79813713

Gearbox brakes at 12:20, please excuse the crap camera location I was trying to find somewhere to put it, noisy diff pinion bearling is a bit annoying as well but will be sorted along with the gearbox.

[Mr Cerbera]

MoonMonkey said:

.....
If this has happened it will mean a new gear set which I think can be circa £1,000, plus the bearings, synchro rings etc.

8 years ago Simon, at Fernhursts, told me that they exchanged duff boxes on their buy-ins for £540 ??