Allison tt series transmission issue

[zlssefi]

Not yet. Most likely early next week. I habe another project that needs done ahead of this one.

 

[Rustyfender]

Well I certainly will be following your steps thanks

 

[zlssefi]

Update! I got into the converter housing today. I thought i was going after the freewheel clutch but then found the splines for the 2nd turbine completely stripped out. I have a hard time digging any further seeing this issue in front of my eyes. Any thoughts guys?

 

[Rustyfender]

Oh Boy did not expect to see that, sorry I do not have any thoughts on it, are you going deeper

 

[zlssefi]

Oh Boy did not expect to see that, sorry I do not have any thoughts on it, are you going deeper

I didnt either, but honestly this takes an hour or two of extra labor out of this job if it is the issue. Honestly i cant see how it cant be the issue, with the splines stripped out there is no possible way the 2nd turbine was giving any power to the transmission whatsoever. The downside is im sure the torque converter prices are more than the 950 i was quoted for the freewheel clutch. If any guys can chime in who know these two stage converters well that would be great!

 

[john hofer]

You need to remove the transmission. the shaft that is damaged drives the freewheel clutch which i think is locked up,the first stage turbine was fighting with the second stage turbine that caused the splines to strip.being the freewheel clutch locked up.
If I were you I buy a rebuild transmission. If the turbine output shaft is damaged than the turbine is damaged. Don't get me wrong it can be rebuild, it'll be close to a rebuilt price.
It may be save to say put it back together and use it the way it is,there is no more pressure on the freewheel clutch for it to blow up.

 

[zlssefi]

Will either of the turbine shafts be locked up if the freewheel clutch is locked? Just trying to properly diagnose without tearing it completely apart. The 2nd turbine shaft is in perfect shape, only the 2nd turbine female splines are stripped. The odd thing is there is virtually zero metal in the filter or sump of the transmission like this happened over a long period of time.

 

[zlssefi]

I guess what i am trying to ask is, how free should the 1st and 2nd turbine shafts spin when the converter is removed? Spin with two fingers? Spin with a pair of pliers? I do know that the first turbine shaft will turn one way but locks when you try to turn it back the other way.

 

[john hofer]

If there's only slow speeds that means that the first turbine is doing its job.
For higher speeds the torque must be low ,the freewheel clutch is geared much higher ,it than starts to grab hold of the second turbine shaft witch in your case is missing so there will only be one speed This is a pic of a clutch that blew apart with most parts in the slump, the reason your slump is clean is that the clutch is frozen onto the shaft,there will be nothing wrong with the turbine except the maybe the second drives splines
The second pic is of the assembly clutch.

 

[zlssefi]

If there's only slow speeds that means that the first turbine is doing its job.
For higher speeds the torque must be low ,the freewheel clutch is geared much higher ,it than starts to grab hold of the second turbine shaft witch in your case is missing so there will only be one speed This is a pic of a clutch that blew apart with most parts in the slump, the reason your slump is clean is that the clutch is frozen onto the shaft,there will be nothing wrong with the turbine except the maybe the second drives splines
The second pic is of the assembly clutch.

I got ya. How far into the trans is the freewheel clutch after removing the converter housing? I have it in the machine stripped down to an empty converter housing now.

 

[john hofer]

You will understand more once you take the transmission apart you only need to remove input shaft cover

 

[zlssefi]

Got it. Once the converter housing is off its basically right there.

 

[Rustyfender]

Is the sprang clutch the same as freewheel clutch? Also, if freewheel locks up, will it strip one of the splines that drive either of the 2 speed torqueconverter

 

[zlssefi]

Yes the "sprag" and "freewheel" are the same assembly. Ive been told that it can wipe out the splines if it locks up because the turbines fight each other. Im trying to get further into this one today to determine if the freewheel is ok or not.

 

[zlssefi]

So i pulled the torque converter housing back about 8 inches off of the transmission today. The freewheel clutch looked in excellent condition and it would allow the 1st turbine driven gear to lock in one direction and freewheel in the other. Knowing how the transmission is supposed to work i was satisfied with this and put it back together. Now i have to wait for my converter parts to come in so i can finish it up.

 

[Rustyfender]

Looks good glad that was all you found.

 

[Rustyfender]

Did you get your parts yet?

 

[zlssefi]

I did. I ended up getting the 2nd turbine assembly, converter pump, all gaskets, seals and lock tabs from Parts Unlimited in Missouri. Tom Hall is the man to talk to. 1300 bucks for everything shipped to my door. They had used and new offerings for almost every part.

 

[Rustyfender]

Thank you for sharing the info. Do you have yours up and running again?

 

[zlssefi]

I havent had a chance to get the new parts installed. Im shooting for this week, maybe tuesday time frame. Ill keep you updated.