Gearbox Shaft - Problems

[Styria]

This is the sort of thing that can happen on high mileage cars. The picture shown is the input shaft from Torque Converter to the front of the gearbox on a 6.9.



You will note that the shaft on the left is completely berift of splines - in other words, there would have been no drive from converter to box, and car not go. The one on the right shows the upper splines being almost razor sharp - the result ? Very close to being stripped. On a good shaft, the top splines should be similar in appearance to the bottom ones. As I said, the result of high mileage vehicles, or perhaps even brutal acceleration tests time and again. Regards Styria

 

[Oversize]

So is there any way to ensure it never happens (apart from parking the car)??? A heavy-duty shaft perhaps?

 

[motec 6.9]

Hi Mark short of buying the TH700 adaptor the same as i have no not really . You may be able to adapt later shaft from 722 5speed but not sure as top version is rated to 1000nm of torque . I asume with my power and torque i will kill mine but i will cross that bridge when i come to it.

 

[Tony66_au]

So is the 450 Shaft the same?

The Auto's on the 116 isn't something I've gotten into yet and a rotten shaft wouldn't be the end of it all for me.

Shame there isn't a HD Shaft option though.....













Mmmmmchikka bow bow.............. Shaft.

 

[Tony66_au]

Actually looking at those 2 examples I cant see why a case hardened shaft wouldn't solve that issue.

 

[Styria]

Tony, 6.9 and 450 shafts are not interchangeable. At the moment, I am looking into looking for a suitable replacement. I should know by Monday. Regards Styria

 

[Tony66_au]

I suspect that a good machinist could mill up a suitable replacement fairly easily Styria, and tempering the unit or case hardening it wouldn't be out of the question.

Id show a good one to a fitter and see what they say.

 

[Oversize]

Sounds like a great idea Tony! Motec I'd definitely consider this, otherwise you may be off-the-road again rather quickly!

I'd also consider screens and magnets in the trans pan to reduce the chance of the whole tranny being unusable in the event of shaft failure. Could their be such an animal as a trans cooler (external) oil filter?

 

[Tony66_au]

Sounds like a great idea Tony! Motec I'd definitely consider this, otherwise you may be off-the-road again rather quickly!

I'd also consider screens and magnets in the trans pan to reduce the chance of the whole tranny being unusable in the event of shaft failure. Could their be such an animal as a trans cooler (external) oil filter?

Sure there is but as Tranny's are so very different re One pump or Two, operating pressures etc id just do the old rare earth magnet on the trans sump x 3.

They just stick to the outside of the trans pan and being rather strong will collect ferrous fur on the inside of the pan.

And when you do a tranny service you just clean the pan and it is done!

As for stray metal? Although im not familiar with the auto id say thats the spline the torque convertor sits on so any nasties will be in the bell housing not the tranny itself.

Tony

 

[TJ 450]

Actually,

Those are stator shafts, the input shaft is what provides drive to the transmission, and is the shaft that "pokes through" that one.

The stator shaft is the same across the board for that series of transmission, in other words the shaft for a 280, 350, 450 is the same. There is one exception though, and that is that there are two versions of it. One version is retained with a circlip and the other type is pressed in with a rolled edge.

I have a brand new Genuine Mercedes part sitting here that is the clipped in type.

Tim

 

[Styria]

Actually,

Those are stator shafts, the input shaft is what provides drive to the transmission, and is the shaft that "pokes through" that one.

The stator shaft is the same across the board for that series of transmission, in other words the shaft for a 280, 350, 450 is the same. There is one exception though, and that is that there are two versions of it. One version is retained with a circlip and the other type is pressed in with a rolled edge.

I have a brand new Genuine Mercedes part sitting here that is the clipped in type.

Tim

....good to hear from you, Tim. From your experience, is the 6.9 stator shaft unique ? Regards Styria

 

[Helmet]

Tim is correct that the shaft in question in fact the stator shaft. The stator shaft so called because it holds the stator in the torque convertor, it is essential for torque multiplication on take off. When the shaft is worn the car is still drivable but will have dramatic loss of torque on take off. In the past I had some made and then hardened. From memory I think the 450 stators are the same and as Tim said there are early and late versions.

 

[Styria]

Hi Helmet, do you still have any shafts and, if not, are there still transmission specialists such as Pendlebury etc. in business - I believe Gordon has retired, but do you have further knowledge ? I will have to look into this a bit more. Regards Styria

 

[Helmet]

Hi Helmet, do you still have any shafts and, if not, are there still transmission specialists such as Pendlebury etc. in business - I believe Gordon has retired, but do you have further knowledge ? I will have to look into this a bit more. Regards Styria

I dont have have any shafts left , however if you need the later type, I'm sure I can source one for you :cheers:

 

[kunbarrie]

have seen this happen to old wide body toyota camrys,low milage and still under 100k waranty,i put it down to a factory problem,i looks like it was put in a lathe and machined down with precision cuting tools,it never ceases to amaze me what can happen to metal in a engine or tranny,when a failure occurs.