I've been having troubles with my 37 clutch for some time now. As per some previous posts, the battle has gone from linkage issues to include fork alignment and the connections thereof to pressure plate issues to throwout bearing issues. I've pulled everything apart a number of times. Replaced the pressure plate, the clutch the throwout and most everything else in one respect or the other. I did everything EXCEPT swap flywheels to the next model and changed everything... and then I even (and finally) did that. 

So here I am with a truly NOS 1938 upgraded flywheel, pressure plate and clutch. It was hard to find anything that wasn't worn out but I finally light on a 4 bolt flywheel to fit my crank but with the heavy 9 bolt pressure plate version which was made for the heavier trucks of the era. I found the appropriate pressure plate and the 10 3/4" clutch all of the same heavy truck vintage. I already had a brand new throwout bearing from a previous unused set so with everything in hand, I proceeded to bolt it all together. 

I didn't fully explain what brought me to this though. As mentioned earlier, I could never get any of the 37 clutch flywheel pressure plate combinations to work without some level of vibration that wasn't there when I bought the car. I won't go into all the details but if it wasn't the pedal shaking, it was the whole engine. I've read how the 37 pressure plate was a bi*ch to get all right but d*mn. I finally gave up, replaced everything with 38 and checked for vibration every step of the way. All good.

So anyway, I now have the 38 truck setup. Everything seems to fit. The newer pressure plate has the bladed fingers instead of the three finger (impossible to adjust) setup that the 37 had. The clutch is wider and has more surface area. I had the flywheel checked for balance and it was spot on. I poked around and even found a pristine NOS clutch fork for the 38 version throwout. I also checked the bearing for the same size inner diameter as the 37 to match the trans input shaft. All is right with the world. OK... in my little world at least.

I'm now at the pedal adjust phase where I want to have a clean non-rattle pedal and as such, a throwout bearing that doesn't wobble on the input shaft of the trans when it's free of the pressure plate teeth. On newer vehicles there is a sleeve that the bearing slides on so to keep it from bouncing around. On the early setups (unless that's the part that was lost years ago) there is no sleeve so the bearing has nothing to keep it from shaking against the shaft. That is unless I adjust it to barely touch the blades at all times. Everything I've read though says that this is a bad thing but everything else I've done says THATS the only way it'll stay smooth.

So that's my dilemma. Touch all the time and stay smooth... or give it the free play the books recommend and the whole assembly rattles. Oh, and if I don't snug the bearing to the blades, I don't get enough travel to fully disengage the clutch and it grinds when it goes into gear.

Final note: the 38 fork teeth do not set centered on the throwout bearing sleeve. It hits a little like the fork to pivot length is just a little too long. But I've looked everywhere I can find and there is no mention of a different fork length (pivot point to fork teeth) for the heavy truck config. There IS mention at the pedal end being a little different to fit the truck surroundings but nothing at the bearing end. The only difference is the different 9 bolt pressure plate config and the more robust clutch diameter.