4WD issue

[Rede]

I bought an 82 chev 3/4ton 4x4 as a winter beater and have had the truck 4x4ing several time with no issues... until friday.

I was heading to work with the hubs locked and in 4hi becaue the roads in town were pretty slick.

Made it about 3 blocks away from home when I felt a jerk/clunk/bang, which I chalked upto the truck just being an old lumber waggon and kept going.
It happened again 1/2 a block later so I slowed down to 40km/h and geared down into third, slipped the tcase into 2WD, then back into 4WD to ensure I had it fully engaged. Another 1/2 a block later it did the same thing.

I pulled over, looked under the truck for anything noticeable but couldn't find anything, put the truck in 2WD (left hubs locked) and carried onto work with no issues.

After work I put the tcase back into 4WD and again, made it about a block before the same jerk/clunk/bang. By this time I noticed that the problem seemed worse or more violent the fast I was going.

I picked dad's brain and he said I should check to see if the front and rear diff are the same gear ratio in the event that someone had swapped the front diff out. He said the rear diff in the older trucks were usually 3.07 and 3.08 in the front meening the front would pull slightly more than the rear when in 4WD...

Any suggestions on how I can verify that these diffs are the same ratio without pulling them apart, or tell if the front diff is the factory one? (maybe via a part number or shape of the front diff cover...?)

However, if the transfer case was binding, wouldn't this load the motor up much more on pavement and bind up soon as I started moving instead of a block down the road?

Can anyone suggest anything else I can check? (with in reason for)

I know the front right tie rod and right lower balljoint are completely fragged as well... could this play a factor?