new here hoping for some advice

[New kid on the block]

Hi guys i have a 1987 heavy half silverado that my brother and i started to work on and we recently ran into a problem that ive not heard of before. When we got the truck it need an entire clutch, slave, starter and flywheel. I got the truck from my dad who sent it to a shop to have the clutch and stuff changed and after he got it back lost interest so i bought it to hopefully be able to drive. The list of stuff done is too long to mention but the issue were having currently i have no idea where to start to diagnose it. The truck wouldnt drive at times and we thought it was the clutch as it would start to drive and then "disengage" turned out to be the pinion gear seal for the rear end and we changed it and it got better then the map sensor went changed that and drove less than a 1/4 of a mile before it started grinding really heavily in the front pulled it back and then started the truck and it will grind in/out of gear in/out of 4x4 with the clutch engaged and with it disengaged the only time it wont grind is when the T-case is in neutral..... is the T-case the issue? If so would the t-case from an 83 heavy half chevy work? Sorry its so long

[cadillac_al]

It sounds like your clutch is not disengaging. It could be rusted to the flywheel or it could be the joys of hydraulic clutch linkage. It's hard to tell if the slave is working because they move so little.

[jjzepplin]

OK. So if the clutch did not disengage he could not get it moving unless he started it in gear and punched it. Pinion gears?
My question is why did he bring it to the shop? 99% of the time the issue at hand is the last thing fixed on the vehicle. "Fixed" is not always fixed. Grinding is always bad! I would pull the tranny side cover and look inside. The t-case should also have a side cover to take a look. Pull the dif covers and take a look. Any shavings or debris is likely the bandit. Pics on here and we will tell you whats wrong. Alone we are fierce. Together we are invincible. Bring it.

[New kid on the block]

We had a new pressure plate throwout bearing and slave cylinder the slave is moving we checked that lol i think the reason it doesnt like to move is due to the rear end not having enough gear oil i had never changed a pinion seal before and didnt know how much fluid it needed i moved it once and that was it. So my mext question is would the t-case or front axle and front driveshaft off an 83 fit my 87? I was told that thenose of the t-case or front driveshaft might be a different length

[mongocanfly]

to clarify a couple things...
post #1...the pinion seal WILL NOT cause ANYTHING to disengage..
post #4...also not having enough rear oil WILL NOT cause it to not move[at least not at first]...
to fill the rear end you fill it to the fill plug and its full....

im still rereading your 1st post and trying to understand it..

if I read it right then....if its grinding trans gears when trying to shift with the clutch engaged then the clutch isn't fully released....if its grinding while you were just driving normal [not trying to shift gears, no clutch mashed] just driving then you have a gear problem....could be any one of ...transmission, transfer case, front or rear axle
is it full time 4x4?

[New kid on the block]

It has 2h 4h N and 4l with manual locking hubs but it doesnt sound like trans grinding and the only time it doesnt grind is when the t-case is in neutral, driving or idling doesnt affect it at all

[Desert_Eagle02]

What transmission and transfer case do you have currently in the truck?With that shift pattern for the t-case, I'm going to guess it's probably an np205.

I know this is kind of obvious but have you checked the oil in both the trans and t-case?

So what I'm getting from your posts is that you get a grinding noise when your t-case is in 4H, 2H, and 4L, but not when it's in neutral? If you put the t-case in neutral and run the trans through the gears does that make any grinding noise?

[akart]

Had the problem where the clutch would work then not. Would either grind gears or had to stop to put into gear and start off in gear and then shift w/o using the clutch. Clutch hyd system was not bled completely and worked intermitantly. The clutch is hard to bleed as so little fluid is pumped and the bubbles go up and down while bleeding. To bleed attach a pump type oil can containing brake fluid to the slave bleeder as the bellhousing w/a hose.Open the bleeder valve and pump fluid up to the master.The bubbles tend to float/travel up. Watch for bubbles and pump till gone/clear,then close the valve w/o letting air into the system.You may have to remove some fluid from the master resivour. Don't pump brakes while doing this. You could think about replacing the slave and master as they are not too expensive and they could be past there service life in an'87 truck.
I did this and have had no further problems for 3 years so far.