97 Dakota transfer case ?

My 97 Dakota with 318, 4x4, 230,000 miles has developed a loud clunk in the driveline while driving. It will clunk and actually shake the truck a little. Could this be the transfer case going bad? The transmission shifts fine with no slipping and has clean, red fluid. Transfer case oil level is full. This does it in straight line driving, not in turns. Thanks for any help.

check all u joints and axles

The 1st thing I would look at would be to see if the rear pinion nut has backed off. Then the ujoints, axle bearings and motor/trans mounts. Then see if any of the body mounts are still holding the body onto the frame. Gene

What joints are in the front drive shaft? Some ifs front driveshafts use cv. Joints on them and when they wear out the symptoms are like a clunk, crunch, binding deal. Make you think you have teeth missing on the ring gear. Easy Enough to pull The front driveshaft.

It isn't a steady clunk, it only does it every now & then, maybe only 2 or 3 times a day.

Check the easy stuff first, don't go directly to the hard parts.
Start with a good visual inspection of the u joints, driveshafts, mounts, mounting bolts and such.