Ok, on to my next problem.  I have this really loud grinding sound coming from either my transmission or my transfer case.  It souunds like a metal on metal type of grind, kinda like if you pulled a piece of metal over gravel....something like that.  Anyway, it does it in all gears, but ONLY when the driveline is torqued.  When i'm going down the road or whatever and let off the gas or push in the clutch and coast, nothing at all.  Nice and smooth.  So, i need somewhere to start, where to look and what to check.  It's not a whining noise either and everything else runs just fine.  Shifts great in all gears, shifts great in the tcase....  Got any ideas guys?

I have quite a few ideas - but not a clue as to what vehicle you're asking about - and it really does make a difference.

Let's start with the universal joints in the drive shaft - slide under the vehicle, grab the drive shaft (rear) and try to twist it - how much movement do you get?  Look closely at the yokes and see if that's where the movement is.

Oh - if it's a Samurai - you might want to do the same thing with the jack shaft that links the transmission to the transfer case.

wow, holy crap!  Yea, sorry about that!  It's an 87 samurai, with the stock 1.3L, 5 speed tranny and the 6.5:1 transfer case gears.....can't believe i forgot all that info!  I really seem to think it's in the transfer case, but i really have no idea.  I"m not a transmission guy, i don't know anything about a tranny or tcase.....  But, the driveshafts seem to be pretty solid.

EDIT: When i bought it, i noticed the sound while test driving it. The previous owner told me that it was the tcase because it was just rebuilt with the new gears.  I was very weary, but him and his buddy assured me it was fine and would get better as it broke in.  The more i drive it and mess around with it, the more scared i get.....  But i will check and recheck all the shafts tonight and report back in the morning.  Sounds like a good place to start...

A Samurai - and with transfer case gears - I was thinking more along the Sidekick/Vitara line, and a possible failed part - I'll hold my tongue from here, but on the principle of what was the last thing you touched before the noise started, then the transfer case IS a possibility.

Does it make the same noise if the transfer case is in neutral and the transmission is in gear?

actually, i haven't tried that.  I'll check into it and report back.

The driveshafts seemed fine.  They had a little bit of play, but nothing i would consider unordinary.

Is the fact that the transfer case is new even really an option?  Why would new gears make this loud of a noise?  And a grinding type noise at that....

Thanks for the replies so far guys!

Is the fact that the transfer case is new even really an option?  Why would new gears make this loud of a noise?  And a grinding type noise at that....

Thanks for the replies so far guys!

Just because the tcase is "new" doesn't mean it was put together correctly.
BTW, tcase gears do not get quieter as they get broken in.  Either the PO is stupid or just flat out lied to you.
I was thinking maybe it is the dust shield on the flanges (tcase or axle), but that doesn't really explain why it makes the noise under load but not other times.  Unless the flanges are loose (the flange nuts aren't torqued down good).

i'm beginning to think the PO did just flat out lie to me!  Guess i should've been smarter.  But oh well, now i just gotta find out what it is.  IF it is the Tcase, i'm gonna swap out a stocker (if i can find one reasonable!) and break down the one in it now and see if i can figure out....

Another thing I thought of....bad axle gears or bearings can make a sound like you are describing.  It is really noticeable when accelerating, or at a light torque load, but won't be nearly as noticeable when coasting or decelerating.
Might check the rear end oil.  If it is really dirty, low, or has metal flakes in it, it could indicate there might be an issue in the rear axle.
Another way you may be able to figure out if it is the rear end is to take off the rear driveshaft, drive in 4x4 (use the front axle to power the samurai) and see if the noise is still there.  If it isn't, then it is the rear axle.  If it is, then the rear axle is more than likely ok.

pretty good idea right there.  Gonna do some real good investigating tonight.  I"m gonna try putting the rear on some jack stands and putting it in gear to see if i can tell where it is by listening.  It sounds like the Tcase.  And my gut tells me that, but, i guess it could be as you described and in the rear end....

ok, so here's the deal after inspecting really good last night.....

Tcase in Neutral, it makes the noise through every gear, getting louder as i go "faster", the loudest being 5th gear.  So, the more the tcase moves inside, the louder it is.  Again, it doesn't make hardly any noise when i let off the gas and coast, or push the clutch in.  The driveshafts are fine, i was actually suprised how good they were, no sloppy joints.  Also drained the fluid in the Tcase, no metal in it, although it was very black/old looking.  So, i've isolated it to the Tcase.  Any idea what could cause this noise in there?  Other that the sound, it runs just fine.  It's not a whine either, its a metal on metal sound, like the gears are hitting the side of the case or something.....These gears are pricey so i'd like to save them.  I have no idea how to take apart and inspect a tcase, i'm not even sure i want to tackle it, but if i can find one i can swap out, i'll have the time to tear into it......so i might try it if you guys think it's pretty easy.....

What do you guys think?

Sounds like they might not have done enough grinding on the interior of the t-case to allow the gears to clear.  When installing the 6.5 and 8:1 you need to grind down a bit of the t-case for clearance.  Not that hard of a job, but be careful as it's pretty easy to grind right through if you are using a hand grinder.  JB Weld can fix the spot you go overboard.  Oh so I have heard... 

Yea, sounds like that HAS to be it. I mean it runs and drives just fine, even at 50mph, nothing, just that loud a** noise!!!  I guess i'll just have to listen to it for awhile....til i take it apart or replace the tcase!!!!  I'd like to have a spare anyway, so maybe i'll replace it with a used stocker and tear this one down and figure it out!  I read the instructions on Trail Gear, sounds horrible!

ok, so here's the deal after inspecting really good last night.....

Also drained the fluid in the Tcase, no metal in it, although it was very black/old looking.  So, i've isolated it to the Tcase. 

If the tcase wasn't properly clearanced, and the gear has been grinding on the side of the tcase, there would be all sorts of aluminum colored metal in the oil.
So from what you say above, I don't think it is a gear grinding on the tcase problem.

Have you looked to see if one of the flange dust shields is slightly out of place or bent?  If it is rubbing against the tcase, then it would make a noise that gets louder/faster with speed.  Although, that wouldn't really explain how it makes the noise just under load....it's not like the flange moves in and out (or at least it isn't supposed to).

i'll look again, but i didn't think i saw anything externally that would be rubbing anything, but i'll have alot of time this weekend to look into it.  I wouldnt think it would be anything external because i had the tcase in neutral and went through the gears and it made all that noise when nothing was moving except the tranny and tcase....Isn't it the flat part(the outside part) of the gear that hits the side of the tcase shell?  If so, it would be a smooth rub and prob wouldn't make many metal flakes, at least i wouldn't think, but that's just a theory...i really don't know....from the pics of the install on Trail Gear, it looks like that gear is smooth on the outside....if that makes any sense at all....