Stiff/Odd clutch pedal after putting an LQ9/NV4500 into my OBS Chevy

[Coburn]

Hey everybody! I'm in the middle of dropping in an LQ9 into my 2000 Chevy K3500 CCLB. Well, closer to the end. But there's one big thing that's got me stuck and not sure about what could be causing this.

So what's going on is I'm using an NV4500 from a '92 Chevy, external slave. For the clutch components, I'm running:
ACDelco 383217 clutch kit (pressure plate, friction disc, throwout bearing)
Sachs NFW1050 flywheel (from a 2002 LQ4 Silverado)
McLeod 8617 Pilot Bushing
Brand new pre-bled master and slave cylinder

So the clutch works, but the major problem is a "hump" right about in the middle of travel. When you push the clutch in, it gets harder and harder until you reach the peak of the "hump", then it gets softer and softer all the way to the floor. The "hump" is right when the clutch disengages.

I haven't heard any noises, and the clutch acts like it should, not slipping or grabbing. This clutch feel is just a major PITA because it makes it very hard to shift without making the whole truck try to buck! I know the ACDelco clutch is the "higher clamp load" rather than the standard, would that cause this kind of clutch feel? Or could it be a worn shift fork or fauly/wrong installed throwout bearing? Maybe a bad master or slave?

Thanks in advanced for your expertise

[Chevydillan]

Worn bearing retainer maybe.

[Coburn]

Worn bearing retainer maybe.

Yea maybe. I dont remember it being work when I inspected it though. Also, it was in my truck before and the clutch was perfect, besides being worn. I'm starting to think its something in the hydraulics, like the slave. Could the hydraulic system cause this?

[Coburn]

Come to find out, it was a bad pressure plate. Its hard to believe that it was defective from the beginning, being new and all, but it was. Replaced it and now all is well!

[gagliano7]

Gad to hear you figured it out. I thought it might be the master cylinder. How did you figure out it was the pressure plate? Sucks you had to drop the tranny again.

[1991SSP]

just finished up lq4 in my 94 model C3500,,, I am having the same issue.. though my clutch was smooth as silk before I removed the 454.. I kept the clutch and pressure plate that was in it,, used the same pilot bearing and the same flywheel that you used...... Im on the fence about dropping the trans in my garage or taking it somehwere to see what's going on with it