I'm getting a LOUD popping sound while in 4hi (haven't tried 4lo), it sounds like its coming from the transfer case. Doesn't matter if I'm going straight or turning, basically anytime I give it some power, it pops/grinds.

I had all the u-joints done about 6 months ago along with a bad front hub. I went ahead and changed all the fluid in the front/rear differential and transfer case. Transfer case didn't look terrible, but was pretty dark; the front/rear diff looked good.

Could it be the chain slipping on the T-Case? Is there a way to check it without pulling it?

Any ideas would be helpful; I'm trying to learn how to do as much of this stuff as I can. Money is SUPER tight right now and I'm also pretty sure my injectors are done (hard/no start when cold, starts when I plug it in, etc).

 

if i remember right when you drain the fluid you can see the chain from the drain hole. take a look in there and with a screw driver and see if it is sloppy. jack up 1 rear tire and turn the drive shaft, that may help too.

i am not positive on that.

i change my fluid all the time when there is nothing else broke

 

I'd say you got the diagnosis right. If it just popping in 4x4 when you power it the chain is stretched. Drive it in 2x4 and carefully in 4x4 and you will get by as long as it is not shedding metal.

 

Drain the t case oil and look for metal. If the chain is popping it will be there.

 

highway has the best idea. i bet you do not get very much fluid out when you drain it. it is easy to overhaul, go to allstategear.com and download the drawings you will need the complete bearing and seal kit, chain, oil pump, two gears the chain runs on, new fork and pads for fork. i can not locate the parts list from the last 03 i did but if i find it i will send it to you. cost is about $600 go back with synthetic syncromesh sae50

 

I have the free spin hubs so my chain only moves when I use 4x4. I have always used ATF+4 in the TC as recommended. Is there something better?