Exedy clutches will not fit on input shaft

[aimso]

My '07 Mustang GT came with an Exedy Mach 400 clutch and while I was engine swapping, I decided it would be a good time for a new clutch. I got a another Mach 400 clutch.

I aligned the new clutch with the alignment tool and tried to put the engine in. For hours, I tried to get the engine back in but couldnt. I took the engine back out and the clutch is destroyed. The teeth (or the parts that mate with the splines of the input shaft) were absolutely destroyed. I figured I messed up, so I bought ANOTHER Mach 400 clutch (#3).

I took my old clutch and attempted to slide it onto the input shaft by hand. It would only go on the input shaft in 3 of the 10 possible rotations (e.g., would align and slide on, but if I took it off and rotated it, it wouldnt).

I then took my brand new Exedy clutch (not destroyed one) and attempted to slide it on by hand and it will not go on at all. The second it hits the splines, it locks up on the input shaft and I cannot get it to slide on. I have tried cleaning, sanding, filing, and greasing the input shaft, but it does not help.


Before you ask, yes I drove the car for thousands of miles with the old clutch with no issues so I know I have the correct clutch. Similarly, the clutches I bought after have the same part number and spline count.

The pictures are: How far I can get new clutch on, measurements of new clutch, measurements of input shaft, proof old clutch at least fits on input shaft.

Is it just Exedy quality control or is my input shaft messed up? I took some measurements with some cheap calipers and there is almost no room for play at all. My old clutch is at least .01" bigger on some of the teeth. Has anyone else had this issue or this there anything I could try? Any advice is appreciated!

 

[86GT351]

My '07 Mustang GT came with an Exedy Mach 400 clutch and while I was engine swapping, I decided it would be a good time for a new clutch. I got a another Mach 400 clutch.

I aligned the new clutch with the alignment tool and tried to put the engine in. For hours, I tried to get the engine back in but couldnt. I took the engine back out and the clutch is destroyed. The teeth (or the parts that mate with the splines of the input shaft) were absolutely destroyed. I figured I messed up, so I bought ANOTHER Mach 400 clutch (#3).

I took my old clutch and attempted to slide it onto the input shaft by hand. It would only go on the input shaft in 3 of the 10 possible rotations (e.g., would align and slide on, but if I took it off and rotated it, it wouldnt).

I then took my brand new Exedy clutch (not destroyed one) and attempted to slide it on by hand and it will not go on at all. The second it hits the splines, it locks up on the input shaft and I cannot get it to slide on. I have tried cleaning, sanding, filing, and greasing the input shaft, but it does not help.


Before you ask, yes I drove the car for thousands of miles with the old clutch with no issues so I know I have the correct clutch. Similarly, the clutches I bought after have the same part number and spline count.

The pictures are: How far I can get new clutch on, measurements of new clutch, measurements of input shaft, proof old clutch at least fits on input shaft.

Is it just Exedy quality control or is my input shaft messed up? I took some measurements with some cheap calipers and there is almost no room for play at all. My old clutch is at least .01" bigger on some of the teeth. Has anyone else had this issue or this there anything I could try? Any advice is appreciated!

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Sounds like the input shaft might be slightly twisted. Common issue.

 

[whitmanink]

if the shaft was twisted, wouldnt you be able to see that?
and if its twisted an .0004 , you should still be able to clock the clutch onto the shaft by letting it follow the "twist"? unless he has a +550 hp car, with a stage 5 clutch ,, i dont see a twisted shaft

 

[JC SSP]

Take the clutch alignment tool and fully insert it in all the clutch disc (old, new, etc.). If the tool goes in all the way with no binding then the issue is with the transmission input shaft.

 

[Midlife Crises]

The fact that the old clutch disk only slips on the shaft a certain way tells there is something wrong with the shaft. Like 86GT351 stated, it is not uncommon for the stock input shaft to develop a twist. It does not have to be abrupt. Just a few thousandths over the length of the splines and the disk will bind on the shaft.