My 2004 town and country cometimes bucks at slow speeds and it is most noticable at times right after you turn like in a parking lot. Also in slow traffic. alos someitms when going up inclines.
I don't know if this helps but there also has been times when going about 5 -10 mph when engine just dies. Dealer alwyas says nothing wrong. Any clue?

Sounds like the torque converter in the transmission is failing. I'm betting as you reach higher speeds the bucking etc, goes away correct?
Are you seeing a Service Engine Light on the dash? If so an error code is stored and can be read with a scanner at Autozone for free. This code may reveal the problem area.

Burried in this article are common symptoms of failing torque converters. Scroll down to "Torque Converter Checks". Disregard the test steps and just look for the symptoms they talk to: http://www.forparts.com/ICtransmissiondiagnostics1.01.htm

Other possibilities are low idle RPM or engine timing could be out of specification. Both of these are automatically set by the engine management system. One of several sensors would have to fail or the engine computer itself (PCM).

I had a mechanic change all the fluids in rear end. He said there are several sections to change. Tis seems to address almowt 90% of the problem.

Get the codes off the engine and post here , the ignition key, turn it to on then off then on then off then on and read the codes that come up in the odometer display , it will say done when finished . Sounds like maybe a bad plug or 2 .

I had a mechanic change all the fluids in rear end. He said there are several sections to change. Tis seems to address almowt 90% of the problem.

Hey shirleyvan - Has the bucking sayed away in the months since since your fluid change?

Also has anyone else fixed the AWD bucking symptom through a rear end fluid change?

The bucking described in this post sounds like one or more of the tires losing traction, like going around the corner on loose gravel, or driving over paint stripes in parking lots, or slipping on wet pavement. If this is the case, the bucking felt is actually the reaction of the Power Transfer Unit redistributing the drive power from the slipping wheel to the others. Remember, your van is "All Wheel Drive" and this type of bucking proves that the AWD system is working as designed. Take it from someone who as owned a T&C AWD for over nine years. What's more, most dealer mechanics are cluesless on the inherent trait.

The bucking described in this post sounds like one or more of the tires losing traction, ...

Thanks for the feedback. But the bucking symptom I get is much different and more severe than the sensation of the Power Transfer Unit doing it's job on slippery surfaces. The bucking feels like the transmission seizing for about a quarter second then freeing up again. It will usually do this 2 or 3 times in rapid succession at about 5 to 10 mph - total elapsed time per episode is about 3 seconds. Once speed increases it does not happen.

My neighbor's AWD Caravan did the same exact thing while still under warranty but the dealer could never reproduce. The number of posts on this and other forums makes me think it's a real issue.

Does this bucking happen when accelerating or when your foot is off the gas??

Does this bucking happen when accelerating or when your foot is off the gas??

It happens when accelerating from a standing start.

Based on that response, I stand on what I said before, your slipping a tire. Check the condition of your tires. All four tires must be matched!! They all must be worn evenly. Periodic rotation is critical on the AWD. You will notice you have a full size spare. There is a reason for that. A mini spare will mess up the AWD system if it was ever put on. Mismatched tire sizes, either on an axle or front to rear, or one new tire with three worn tires is a strict NO-NO on the AWD. I suggest you go out and buy set of four matched tires now and see if this condition goes away. Let us know what you find.

The tires are Michelins (matched/regularly rotated) with about 15K on them.

Another reason I don't think it's just the AWD reacting to traction loss is that it started happening at about 50K miles. Never happened once before 50K.

I will be changing the two AWD fluids soon and will post whether it has an effect.