93 f350/ 4x4/ zf5/ 10.25/ 4.10s
Backstory- traded for the truck, 280k miles but the speedo is broke so not sure of actual mileage. Has some loud gear rollover but I assumed that's because of the smf previous owner installed. I've put about 600 miles on it since I bought it. Changed all fluids as soon as I got it. It been running fine for past month, no problems at all.

Problem- other day headed back from Kansas going about 65 down i35 it felt like I hit the brakes, then jumped a bit and made a squeeling noise from the Trans area then felt like I hit the brakes again. I pushed the clutch in and got off the road. As it was rolling to a stop it felt like It was in gear with the clutch out. I shut the truck off and checked everything over. Found no problems. Got back in and started it but the shifter felt weird and if I let clutch out it would stall. I thought it was stuck in gear so I shut it off and moved the shifter back to 5th and back out into neutral. Shifter now felt normal and engaged all gears. I drove it to the rest stop about a mile up the road in the e lane to a rest stop and called a buddy to come haul it home. Truck runs and shifts fine now. Drove it on and off trailer and into my shop. I drained the fluid, no shavings or metal debris besides a spring which I'm guessing was the reverse lockout spring. Removed pto covers and shifter and found no broken gears or cracked shift rails or anything out of the ordinary. I can tell it has been apart (lots of silicone on the case and covers) what could be the problem? I'm stumped I don't want to pull it if I don't have to.

 

Wondering if maybe couple pressure plate bolts came loose

 

Pressure plate and clutch are good and tight. Transmission is out and apart. No visible signs of damage to anything. I am missing on of the pins that puts pressure down on the 5th / rev shift fork shaft. Hoping someone will chime in here......

 

You may want to check the transfer case as well. Lots of problems that seem to be transmission related have been due to a bad t-case. I helped a friend replace his ZF5 only to find out the problem was still there.

 

I guess I should give an update on the problems.....I went ahead and pulled the Trans the rest of the way apart and found that the bearings in two gears on the mainshaft are toast, sounds like they're full of sand when I spin them. I'm guessing the combination of those bearings and lack of detent on the shift rail caused the Trans to lock up. I disassembled the tcase as well and everything there is good, bearings are fine and oil pump is in tact. So it looks like I'm going to need a bearing kit and seals for everything and I mas well replace clutch and rear main while I'm there so I don't have to pull Trans again.