Here something I cant quite figure out on my 95 v8 4x4.

From a stop, if I take of under light acceleration I wont feel anything, but if I give it enough gas to get up and go, I feel a little "clunk" for lack of a better term, and I hear a lite clank. Feels like there is some slack somewhere in the drivetrain that finally tightens up. After you get the "clunk" out of the way, shifts into all gears fine, all is good.

When I stop, and start back over in low, leaving a light, same deal. Almost feels like when you have something loose in the bed, and it slides back and hits the tailgate when you take off.

Whats the easiest way to determine if I have play in first gear, or play in the rear end itself? I thought it was the U joints going but I inspected them for slack and they seem fine. It almost feel as if the rear axle is shifting back and forth because some times you can travel as far as 15 ft before the lite clank and hit occur.

Anyone else have this symptom? Doesn't make any loud noise or cause big problems, just trying to find out what it is so I can dive in. Thanks!

 

My 1995 Dakota 4x4 does the same thing. When I put it into drive or reverse or start from a stop or even let off the gas after accelerating. The problem is not the u joint, it's the ring and pinion gears in the differential that are worn out. It shouldn't hurt anything, it's just annoying. I wouldn't worry about it cause it probably won't break any time soon and trying to change those gears can be a pain. I've been keeping an eye out for a 1st gen Durango rear end for my truck (someone else on here already said they did the swap) cause it's easier to change the whole rear axle assembly than to change the gears.

 

I should also add (to actually answer your question) to find out for sure if it is the rear end park the truck on flat ground, put both the transmission and transfer case in neutral and get under the truck and try to turn the drive shaft by hand and look for any play.

 

Thanks for the quick answer

 

I have had the same condition in my '95 4X4. At first I thought it might have been a defective limited slip unit and that somehow under moderate acceleration the spool "overwound" until it "caught up" with the other axle (as can occur when going around corners). After having the LS unit replaced by a reputable shop with an Auburn unit, it did exactly the same thing. It appears that Auburn units don't like synthetic gear lube and therefore the bias from one wheel to the other changes when going around corners (It doesn't do it straight line). There is a slight but quite noticeable "clunk" when the bias returns to straight line and from that point on--until going around corners or backing up in not a straight line--it remains quiet.

My solution, try adding some friction modifier to the differential, or better yet change the lubricant completely but be sure to add the recommended friction modifier. See if that doesn't help.

 

Every dodge truck that I have owned has done the same thing. Just a dodge trade mark like Chevy’s and popping steering columns. Yes it is in your rear-end (most of the time). You can pull the back cover off of your rear diff and hold your drive shaft still while the rear tires are off the ground and move the ring gear back and forth to feel the slack. This slack which is called “back-lash” set up with 8 to 12 thousands of an inch when built. What causes the clunk is too much back-lash. This is more than likely your problem. Also check the spider gears (inside the carrier) just watch them as you move the ring gear back and forth and watch for slack around that large pin in the center. This pin will wear down if you do a lot of burn outs or off road a lot due to one wheel spinning and the other not. This is the fulcrum that allows one wheel to spin while the other moves slower or stops completely. Notice there is no bearings here. It is one hard part against another with only oil to keep it from wearing. I have rebuilt several of these rear diff when I worked at the dealer ship. Just replace the oil (I recommend synthetic oil) and let it go until it goes out.