14 replies to this topic

[PACINO]

A friend has broken a drive shaft when he was coming from a meeting. This seems incredible. How can this happen?

[nicklouse]

Not where they often break. Clear images of the ends and the fracture edges. Might give a clue. But best take it to a specialist. I would guess there has been an impact around that area some time in its life. Most failures are on the recesses for the C clips.

[stuart bowes]

it's not completely unknown, I saw someone snap a half shaft during an auto test once.. but that's very extreme handling situation it's unlikely he was driving anywhere near that hard on a normal road ..

 

they can wear over time, for example if the splines dry out and it cant move in and out smoothly to deal with up/down movement then it can put extra stress on the metal 

[PACINO]

I only say one thing. This seems like a scam to me. I had always thought that those bars or axles were solid and not hollow inside. I don't know where he bought this, I'm going to ask him. Breaking this piece is super dangerous, because if it happens while driving, you can kill yourself.

[Spider]

It's an odd type of break, not just for where it's broken, but the type of breakage.

The Drive Shafts are 'soft' and only hardened on the splines.

 

The way this Shaft has broken, the shaft is hard - little wonder it broke where it has.

[Rorf]

I only say one thing. This seems like a scam to me. I had always thought that those bars or axles were solid and not hollow inside. I don't know where he bought this, I'm going to ask him. Breaking this piece is super dangerous, because if it happens while driving, you can kill yourself.

 

This explains the problem - he says the shaft is hollow

[stuart bowes]

again not totally unknown

 

https://forums.tdicl...-better.234357/

[PACINO]

again not totally unknown
 
https://forums.tdicl...-better.234357/

Cheers Stuart! Great talk. There are mixed opinions. I particularly prefer the drive shaft to be solid and bend, than to be hollow, light and in a hit against a stone on the road, it breaks and I lose control of the car and kill myself.

[stuart bowes]

yeah that sounds like a pretty reasonable choice lol

 

I'm not pretending to be any sort of expert by the way, I was just curious myself so I googled it.  from what I'm reading though sometimes part of the reason is one can be hollow to even out the effects of unequal shaft lengths (presumably shaft twist, torque steer, etc) but that isn't an issue with the mini of course having a central diff

 

I'm assuming from the reactions of other people above that generally the shaft being solid is standard on a mini? the ones I took off mine certainly felt heavy enough to be solid anyway

 

I was just pointing out if he/she (or a previous owner) bought and fitted an aftermarket shaft it's not necessarily a 'scam' if it's a hollow tube, although perhaps the type of metal used is low grade or poorly chosen, etc 

Edited by stuart bowes, 04 November 2022 - 12:34 PM.

[PACINO]

Waiting for some more information, this guy tells me that he bought the set second hand, and it wasn't in the best condition. In fact, the drive shaft that broke was vibrating, so it wasn't straight at all.

[GraemeC]

It is an odd failure.

I’m not sure a breaking driveshaft would kill you though, you’d just lose drive. It wouldn’t spit you into the scenery.

[PACINO]

I don't know if it would kill me, but thinking about it, if the drive shaft breaks, one wheel will stop turning as it has no traction, while the other will continue to turn. The car could turn or spin. Maybe you don't overturn or crash, but the scare could be brutal. Of course, if you go 20 miles per hour, surely nothing will happen to you. I'm just going much faster.

[sonscar]

With an open diff neither wheels will drive if a shaft breaks.Steve..

[stuart bowes]

Id be more concerned about the 2 broken ends of the shaft now spinning wildly around in the engine bay to be honest

 

I suppose if you were mid corner at the time driving like a total lunatic then the sudden change of composition could cause some interesting handling and no doubt the sudden noises would cause you to require new pants at the next pit stop

[PACINO]

"new pants at the next pit stop" jaja