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Hello everyone,

My van is making a clicking or banging noise only while accelerating.  If I put it in drive and hit the gas with my foot on the brake it doesn't make the noise, but when I start to release the brake and the rotor starts to spin it makes the noise.

Here's a link to the video of what it sounds like http://www.youtube.com/watch?v=u3AIXCtgdtE

Any help would be very much appreciated.  Thanks!  

I think you need to drop the pan and see if you have any chunks of metal in there.  

i would like you to spin one wheel by hand...  engine off.. transmission in park... ..  both front wheels in the air..  

see if the CV joints are making the noise...

does it change noise when you turn the wheel sharp and spin the wheel..

i would also like to know.. if you can...  step on the brakes....  with the hood open.. clear area in front of the van and behind it.. somebody standing to the side of the engine compartment..   for 5 seconds max.. in drive.. hold the brake and apply the throttle slightly.. see if the engine shifts ... do the same test in reverse... does the engine shift ...   when i say shift.. there are torque struts that counter the torque of the engine when trying to move the car...    look for broken motor mounts..

if you don't get any noise when the wheels are spun by hand in different directions..    try with one wheel in the air.. and the transmission in neutral..  spinning the drive gears in the transmission..  

I just replaced the cv axle on both sides and that was after the noise started.  I was under there checking everything out and they were in pretty bad shape so I figured I'll replace them and if that corrects it great.

I did forget to mention that when I'm driving 40mph or above and I press the gas pedal it makes the noise and the van vibrates pretty badly.

It doesn't make the noise when I spin the wheels in all the ways you mentioned.  I can hear what sounds like lash coming from the pan area when I rotate the wheel back and forth.

Could it be a broken mount somewhere?  The motor does move quite a bit when I have the brake pressed and I hit the gas.

One other clues is when I'm on the highway and I hit the gas hard as if to pass someone and the trans downshifts the clicking gets faster immediately more in time with the engine rpm's and not how fast the wheels are rotating.

This is driving be crazy.  Thanks for your help!  

How many miles on that trans? The engine doesn't appear to be moving too much. The noise seems to be coming from the drive chain area under the channel plate.  

The van has about 160,000 on it and I had the trans rebuilt at around 90 or 100K.

And I made a mistake, it will make the noise even if the wheels aren't rotating.  If I hold the brake firmly and really push the gas pedal it will make that popping sound.  It sounds almost like a gear is worn and it's skipping teeth.

The fluid seems clean, no metal chips or filings when I check the dipstick.  

broken parts will be in the transmission pan..

only dropping the pan will let you know what's in there..

(the transmission pan has several quarts of transmission fluid in it.. and a transmission filter..  just to let you know before you start pulling bolts only to find a HUGE mess on the ground)

plan on another transmission..  its probably toast..  sorry..

can you post a year.. make and model.. its hard to tell by just the driveshaft video..  

It sounds like the drive chain is too loose and its jumping teeth on the driven gear. I don't think i've ever seen a chain loose enough to do that but it sounds like thats what might be happening. Especially since the noise corresponds to engine rpm's.  

So a new trans is in order you think?  

the proper way to go is to pick up a transmission filter kit..4 quarts of fluid.  
drain the transmission fluid as you drop the pan..    inspect the inside of the pan for debris..  

does it make the noise.. with the tires on the ground..  and the brakes locked...   as calipers can allow some movement when the throttle is depressed when the wheels are in the air..