Trans=NV5600 (Original 95,000 miles) Fluid changed 20K miles ago with Amsoil
Clutch=SB FE Single Disk (70,000 miles) No slippage at all.
Clutch Hydraulic=Stock (original 95,000 miles)
Shifter=BD Short Shifter

At times.....hot or cold, it will NOT go into 1st or 2nd at a stop, or when slowing down and need to down shift into 2nd or 3rd. Its like hitting a solid brick wall...it just will not shift into those gears. So I go to 4th or 5th and have to slip the clutch, and try not to get t-boned in turns or other similar situations.

Other times, it will go into the gears, but still feels like I have to use more effort than before to get into the gears.

There are zero noises coming from the clutch. The clutch pedal has about 1/2-3/4 inch freeplay at the top of the travel. The pedal isn't mushy.

Where do I start with this????

I'm about to open up the PTO cover and take a peak inside the tranny, and service the tranny oil. I was going to wait until the 100K mile mark, but its getting worse

 

I'd start by changing the fluid...mine doesn't like fluid that has more than 20k miles on it...mine also doesn't like Royal Purple or Amsoil. I use, and have had the best luck with, with Red Line MTL.

And if it does it once in a while, could it be the pilot bearing not releasing smoothly?

Next time it does it, release back to neutral, pump the clutch, and try grabbing the gear again.

 

I'd agree with Steve on the pilot bearing goin south on ya or the Hydraulics gettin weak. The fluid would have to be dog nasty to actually hang up gears. Dirty fluid just chews up parts more then anything and you will never know it's happening until somethin gives.

I had a case of Headupass disease twice on mine. I installed the new Cutch and then also rebuilt the tranny at a later date and both times should have replaced the throwout/ pilot bearing and never did. For the small cost of the new bearings and already havin it apart I will never not do it again cause I know mines bad now and to change it I have to pull everything back out again.

 

Mine does exactly what his is doing when the fluid needs changed...it comes out looking new at 20k. It is NOT a dirt/contamination issue...it is a SHEARING/VISCOSITY issue.