Dan, I think you need to set the mainshaft/counter shaft clearance to replace the input shaft. The input shaft is pretty much the first thing to go into the case so you have to take the tranny almost totally apart.


I don't think I am missing anything Matt.
In Dans case it does not make the slightest difference which spline stripped as both input shaft and clutch are scrap metal. As soon as the fit gets sloppy (the softer metal in the clutch splines probably gets deformed first) both sides get the **** beat out of them and round the splines over. Sounds like Dans stripped completely which is the result of that slop in the worn splines (or just plain over-powered the spline). The spline area of each clutch disc of the McLeod is only 5/8" thick where the spline area of a single disc clutch is 1 1/4" thick. You want as much surface area to spread the load over as possible. The dual discs have to fit in the same space, so they have to make the spline area smaller on each disc to fit them in. This is why they beat the **** out of the input shaft. There just plain is not enough surface area to spread that kind of force.
The picture I showed shows 2 skinny marks from the 2 discs. If that had been a single disc, the mark would have been as wide, and maybe slightly wider than both marks together. Try looking at the clutches sometime and you will see very clearly what I mean. As I said, I would rather use a single disc. I have blown up about 5 clutches now and never hurt the input shaft. Much rather spend $100 on a new disc than rebuild a tranny.

 

cory on a T56 the cover comes off on the clutch side of the tranny so the input shaft is like the first thing to come out. im gonna take a look and see how hard it looks to be.

 

Ya, I know its a front loader but I had thought you had to pull the guts out with the front cover then take it apart the mainshaft from back to front. Never had a T56 apart before though so I am just going from what Ive seen in pics. Would sure be nice if you could just unbolt the front cover and slide a new input shaft in but that sounds way too easy . Either way with a new input shaft you will likely have to check your clearence between the input shaft/counter shaft gears.
Make sure to get a good rebuild manual and read through it for shimming specs and alignment specs before opening it up.

 

Ok see I didn't know the Mcleod had such tiny disks in a sense that their splines are only 5/8th thick as apposed to 1 1/4" thick on the single disk, never measured it just assumed the dual disk setup had just as thick disk but two, well in that case yes then the dual disk set up is flimsier, especially when you consider that this is not a perfect world and that there is always some lash inbetween those splines, so in some cases one disk may grip and start driving the input shaft while the other disk just clamps and does not inflict any force to the input shaft, I'm sure it happens when you dump the clutch real fast as this is not a perfect world and one disk might end up just for the ride if you see what I'd saying, then you're totally screwed LOL.

I've put a Mcleod together and I must say that it's all nice when you put it together but it does make you wonder, well what if this disk locks first before the other, or what if this disk has less clamping force then the other especially over time, I guess thats why dual disk is not recommended for the street.

But then again, less rotating weight will help keep this from happening durring every impact when you dump the clutch, but the whole dual disk set up just seems flawed for everyday street use.

 

well i finally got ahold of Mcleod today, and he says there are 2 reasons the splines would fail like that, cause he says it would not be an installation problem if it last 25,000kms. he says it would either be a problem in the hardening of the splines on their end which he says is unlikely cause after a year they would have had a few more cases already, or he says it is driving techniqiue which i say is bull, he never went into to much detail as to what he went by it other then something about being on and off the throttle or hard downshifts, and in either case did not happen here.

in the end im send the discs down to them and they'll take a look at what they think which will obviously come back being them or the product not being at fault here, but he said even if i have to replace them the can replace the inner hubs for 30 bucks per disc so not to much money out of my pocket, it is just the input shaft that im still pissed about. still havent gotten a price on one.

anyone know any places that sell stronger input shafts, i think D&D performance does im gonna give them a call. anyways if you know of any others let me know. hope fully i can get all this fixed up for around 500.00 even if it is 500 more then i would like to spend on it.