big bang

[copilot]

Driving along today when all hell let loose. Literally. Bang, reduction in power, clutch in, caltter clatter below deck with clutch in, breaked to a halt. Engine sounded fine. Slowly selected first gear, slowly let clutch out, car moved away slowly up to around quick jogging speed. Then the banging, thumping & clattering started. Nursed it half a mile at walking speed with no problems. RAC man says back axle and drive shaft look complete from the rear to where it dissappears out of sight above heat shield. RAC man dropped car off. It started fine, selected gear fine, clutch feels fine apart from banging dtarts at quick walking speed. Any ideas? sounds expensive!

[blackspider]

Sounds like a drive shaft/diff failure possably a propshaft UJ-you need to get it into the air and wheel free and try it,maybe have to drop the prop heat shield down-dont get alot of trouble with gearboxes.

Edited by blackspider on Sunday 26th November 22:49

[350matt]

Presumably not related to engine speed but increases with road speed?

In which case something either caught up on the prop, or the propshaft joints breaking up or a drive shaft breaking up or the gearbox could even be the diff ( although thats unlikely)

best to get it in the air and have good look underneath

Matt

[blackspider]

Snap

[BCA]

Drive shaft, diff end, by the circlip, probably sheared completely.

[FUBAR]

Having had both drive shafts go (one on a rolling road and one on my first run at the Austec Santa Pod day)in the past 12 months Id get that looked at first.

[rev-erend]

I noticed that Clever Trevor is doing an uprated drive shaft..

[GreenV8S]

If the half shaft fails then the remains may look OK but the half shaft will move around if you push it.

[HarryW]

rev-erend said:

I noticed that Clever Trevor is doing an uprated drive shaft..

Thats good to know .

[Alistair H.]

mine did this at a track day... turned out to be gearbox failure.... all thre teeth were stripped from 3rd gear. just same...fine when doing 2mph, as soon as went any faster then clatter clatter clatter.....

[NHyde]

Happened to me three weeks ago , cruising on the M5 , 5th gear had gone .

[copilot]

I will have a look underneath. RAC guy did look but he didn't touch! I'll jack it up and see if either of the wheels will turn by hand when in 1st gear (although i've not tried gears 2,3,4&5, it does deliver power to the ground when in 1st and and reverse). I had presumed that it was one of the drive shafts, 1/2 shafts or whatever you call them, only because the car was drivable at a very low speed and the banging increased as speed increased (even when free wheeling) It was as though something was thumping around under the car. I had disregarded the gearbox, although I was not convinced the banging/clattering was from behind me, sounded more like nearer the front.

[TON70]

blackspider said:

Snap

An appropriate choice of word??........lets hope not

[copilot]

NHyde said:

Happened to me three weeks ago , cruising on the M5 , 5th gear had gone .

Looks like you were right Neil. New clutch and fifth gear!

[gazzab]

Took a while to fix !!
%th gear goes cos it is used for opening the way to reverse and it is not that strong anyway.

[copilot]

gazzab said:

Took a while to fix !!
%th gear goes cos it is used for opening the way to reverse and it is not that strong anyway.

Right again. This appears to be a steep learning curve.

[HarryW]

gazzab said:

Took a while to fix !!
%th gear goes cos it is used for opening the way to reverse and it is not that strong anyway.

What gear is recommended by the cerbera massif if 5th is dodgy

[Steve_T]

I've always taken Pete H's advice to use 1st to line the gearbox up before going into reverse, since the synchro on 1st is less of an issue to lose than 5th. Other than that, when it goes rebuild it stronger I suppose.

Steve.

[FUBAR]

I normally preselect 1st or 3rd, rarely 5th.

Of course you can go straight to reverse but just let the clutch out ever so slightly until it pops into gear.

[mars]

4th isn't even a gear, so is supposed to be strongest. It's also the easiest to get into when stationary on mine, so I wizz into 4th then reverse. It stops the gearbox idlers from moving so you don't get a crunch.