Just put in a used transfer case in my 1987 chevy half ton 4x4....and now it wont go in any gear???and also theres no fluid in transfer case .......should i add some fluid would that help???

Absolutely add some fluid. You will destroy your new/used transfer case in a heartbeat running it on no fluid, especially since it has likely been out of a vehicle for a little while and completely dry. To be honest, you are probably lucky you never got it in gear, if you did, you would probably have about a handful of metal-flake dust now in the bottom of the case and it would be gone forever. Also, transfer cases do not usually have any kind of dipstick to check the fluid level, in fact I have never seen one with a dipstick and I have worked on cars and motorcycles as a hobby since I was 12 and I am now 44. Somewhere on the back of the transfer case (usually back, but you may have to look around it a bit) there will be 2 plugs like the ones you see on the bottom of your oil pan for your engine. Often they are in relatively the same place or at least same side of the case (sometimes not though). One plug is higher up than the other. The lower plug is your drain plug for when you want to change your fluid. The high plug is your filler hole and check hole. Typically, you would use a pump bottle or siphon to get fluid into the hole. You should typically fill it up until the fluid level is just below the hole and just starts to leak out of where you are filling it (remember however that this fluid is thick and can seam like it is dripping out but is only clogged up a bit taking its time to drain down a little, make sure it is full by sticking your finger or ? in the hole to see if the fluid is just below the hole, under filled or way overfilled will ruin the case as well, although it is pretty hard to over fill it when it starts leaking right at you). Now as far as the correct fluid, hopefully have the original owners manual and that will tell you exactly, if you don't, do an internet search to find the correct type. Some use Dextron (II) even though it is a ford whose transmission usually uses Type F, I don't think I have ever seen a TC use Type F but it is possible, others use gear oil or hyper lube and there are various weights and full, partial, and non-synthetics as well. Search until you have the right answer, you do not want to put the wrong fluid in or we will be right back to the beginning of this explanation with the handful of metal shavings again.
Good Luck
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