Driveshaft up through gearbox and into fly wheel

[ericlovesbeer]

hi everyone
I have had my M3 8v GTI for 2 years and have had nothing but problems but the latest one could be the last straw!!!!!
the car had been making a noise similar to a worn wheel bearing for a couple of months so i finally got the bearing changed on front nearside wheel.  The noise continued and after another couple of months had gone by i started to get a drip of gearbox oil on the drive. The noise continued to get louder whilst driving and a couple of weeks ago whilst driving I smelt the dreaded smell of burning gearbox oil.
To cut a long story short after getting it to a friends garage he took the box out to have a look and discovered that the driveshaft had broken and gone upwards through the bottom of the gearbox casing and out through the top of the casing (avoiding all the gears). It had then come to rest against the fly wheel knocking out at least two teeth!!!!!
Firstly does anybody have any ideas as to how this could have happened and secondly how much am I looking at to correct the problem ( i have been quoted £400 - £600 by my mechanic mate depending on the price of a 2nd hand box)? The clutch is also slipping so will need a new plate........
Any advice would be gratefully received.
P.s the car has had a MII 2 16 V gearbox fitted about 18 months ago after the original gave up. Could the driveshaft have been damaged at this point or is it possible that the guy who changed the wheel bearing might have damaged the shaft.

[adyh]

Very Strange , the price looks about right for the gearbox. If you're changing the gearbox you may as welll change the clutch anyway .

[Len]

Fair price.

That kind of failure could not have been anything to do with wheel bearing!
As it was a second hand box and probably didnt have the correct diff in it then there's your problem!

If you were doing any kind of speed when that happened then you are lucky to be alive! A broken drive shaft can go anywhere or it could have locked up/siezed the engine and an emergency stop like you have never seen!

[ericlovesbeer]

yeah the funny thing is that I cannot even recall when it could have happened and how the car could still drive as if nothing was wrong. the only outward sign of anything wrong was the noise coming form the front of the car which sounded like a wheel bearing and the drip of gear box oil that eventually led to a bi leak which is when i took it to the mechanic to investigate........

[EvilScotsman]

has anyone else driven it and maybe smacked a kerb while cornering, shoving the cv inwards?

[monzablue16v]

Get a decent second hand box and drive shaft, theres no point rebuilding it really, well there is but there isn't if you know what I mean! I've just done/doing mine due to it going bang and I went for a 2nd hand box far far cheaper

[ericlovesbeer]

just got my car back today total cost £600.........

3 in 1 clutch £99
Box  shaft (joint) & flywheel   Ã‚£300
labour  £180   6 hours

did i get a good deal???

also he has put a low mileage gearbox in but its from a 1.8 golf.  is this ok??