I have little knowledge - so bear w/ me on this one:

'94 Ranger 4x4
150,000 miles - original owner

Little use of 4WD - until snow this week.

Loud frequent clunk in rear end when using 4WD

Less obvious when not in 4WD - but there once in a while

Where do I begin w/o getting the shaft on this one - femme problem potential - and I know that regardless of gender, those who are not auto-smart have to pay someone who is.

I just need to be educated, please, so that I can recognize a shaft or a reliable helping source.

Thank you so much!

Are the all 4 tires the same size and are you on dry pavment in 4x4 at all?

All tires are the same size, and I was disengaging 4WD before I ever got to any dry pavement. Noise was worst, and quite loud when in deepest slush/mud. However, even when it wasn't having to work so hard, I was still getting an occasional clunk.

pull pumpkin cover(the round thing) check ring and bull gear for chipped/cracked teeth, check u joints. If it doesnt feel driveline related check suspension components, sway bar links,spring bushings. That truck should have torsien bars. They would go from the front suspension to a brace that runs from frame rail to frame rail. the bushings on the frame go bad and clunk when turning or going over bumps, sometimes both sometimes one or the other. Try those things first

pull pumpkin cover(the round thing) check ring and bull gear for chipped/cracked teeth, check u joints. If it doesnt feel driveline related check suspension components, sway bar links,spring bushings. That truck should have torsien bars. They would go from the front suspension to a brace that runs from frame rail to frame rail. the bushings on the frame go bad and clunk when turning or going over bumps, sometimes both sometimes one or the other. Try those things first

I would check the Universal joints before I went into the differential. My 1992 2-wheel drive Ranger would clunk when I took off, and when I slowed down (sometimes). I turned out to be the U-joint on the rear-end side of the driveshaft. I replaced it myself for the cost of the joint, which I don't remember how much that was. Of course, with yours being 4X4, it could be a number of U-joints. If you could go underneath the truck and shake the driveshaft at the U-joint then, you might figure out if thats the problem first. It should shake a little, but if the U-joint is bad, then it will shake quite a bit.

It actually sounds like the 4 wheel drive isn't dis-engaging after use. I think that you have to drive about 20 feet before it really dis-engages. I have a 1997 Ranger 4x4 that does about the same thing. I can back up like above, and it solves the problem. possible check: hubs. the u-joints are something to look at if this doesn't solve it though.

I say ditto on the u joints if its coming from the back. Maybe not broken, hopefully just not tight.

Thank you all so much - I haven't had time to investigate further - but your help is very much appreciated. I will come back w/ the "answers" - as soon as I have them.

Just got rid of my 94 4X4 got an '03. The CLunk you hear is loud and annoying. This nois I heard on my truck and this is the situation. The noise is the drive train kicking out of 4 wheel. there are teethe that mesh when you drive forward. These teeth DO NOT disengage all the way on older Rangers. untill you hit dry pavement then !CLUNK!

Try this, worked fine on mine and the dealer will agree. when you take it out of 4X4 back up about 10 feet or so. this will disengage the hubs.

The sound that appears to be coming from just underneath you to the rear is the drive shaft releasing the energy when the drive train finally disengages.

Hope this helps

You might also change the fluids in the transfer and front end, even if you don't 4X4.