Automatic Transmission Noise / Issues

lamb686

lamb686

I like torque.
Joined
Aug 4, 2013
Messages
10
Alright, the transmission started slipping on the way home one day shifting into 3rd when getting on the highway. I could barely get up to speed, or make it up even a slight incline/hill. Got it home and once stopped in the driveway it felt like a really bad torque converter shudder but while standing still on the brake. I could shift in and out of reverse or drive and there was no engagement until the truck was revved and it would only creep and shudder.

Next morning I go out and start the truck cold, it would engage 1st and reverse I drove up and down the driveway, after idling for about 15 minutes back to the no engagement/shudder. So I pulled the pan and found no metal and just the average amount of clutch material. Pulled the valve body and saw nothing, except for I could pull the apply arm down about 3/4" from the 1-2 servo. So I adjusted both bands, both of which were way out of adjustment somehow. I thought that would be the noise I heard.

I blew out all ports on the valve body and hit the ports with air and watched the servos, bands and heard the piston work. Put it all back together, filled it with fluid and drove it 5 miles with no issues shifts just fine holds power just making noise. I know it wont last but not sure what is going on here.

The noise can only be heard in park and neutral, when I put it in gear the noise goes away.

* Fluid never got hot on the gauge around 135-140
* Fluid never under or over full
* Fluid is fairly new maybe 5k miles, slight burnt smell still bright red on the stick
* Have not checked line pressure at any of the test ports yet
* I did pull a line off the cooler to make sure the pump was flowing fluid (1qt or so in 20sec per service manual)

Here is a quick video that captures the noise quite well as it is actually magnified in the video making it seems louder than it actually it. Noise is definitely from the flex plate, torque converter, pump area.
[ame="http://www.youtube.com/watch?v=XWJpQbNzS3E"]http://www.youtube.com/watch?v=XWJpQbNzS3E[/ame]

If anyone has any ideas or insight that would be great. I know the tranny will most likely need rebuilt Ive already purchased another one to swap in just wanting to learn and figure out what went bad and why. My initial thought was either the torque converter or the pump went bad being as it was slipping in every gear, hard to imagine both clutches going bad at the same time.

Thanks, Dan.
 
Not sure why but my signature did not show, Transmission is a 47RE in an 01 qclb truck.
 
my money is on converter. Especially if its currently stock.
 
I bought the truck with whats there but I am pretty sure its not stock, the converter is painted a dark silver/gray color and under the paint looks like a bright aluminum color. I was told it has a suncoast valve body and suncoast converter but I cannot be sure. Any way to actually test the converter to be sure that is the problem, other than just swapping in another one? I got what looks to be another aftermarket torque converter with the used tranny I just bought. It is painted black with no stamping on it other than a letter and four numbers.
 
I'm listening on my phone and its hard to hear but it sounds like a broken Flexplate or loose converter bolt
 
With a broken flex plate wouldn't I have a bad vibration?

I will pull the starter and check the torque converter bolts and flex plate from there. Through the inspection cover the flex plate looks fine.
 
Dont pull starter, theres a inspection cover on the pass side of the adapter plate to access the converter bolts. Remove the half round inspection cover on the bottom of the transmission first and check for shavings
 
Alright will check for the other inspection cover later today, but there is no shavings or fluid or anything in the bottom.
 
I would bet its the TC. I had a known good TC start doing that for no apparent reason right after i swapped it in a truck. Everything was tight and when i swapped TC's again it was fine.
 
Torque converter bolts were all tight, started truck and noise is now present in gear as well as park and neutral and is slow to engage any gear. Truck wants to just shudder whether on the brake or just idling forward/backwards in gear. I will be pulling the transmission and swapping out the torque converter soon as the weather breaks a little bit.
 
Alright, I swapped a good used torque converter in over the weekend. Fired the truck up no more noise, drove about 60 miles with a sloppy stockish torque conveter with the edge off. The same exact noise is back but as of now is going away after the fluid gets to about 120 degrees. I guess everything will be coming back apart, something is causing the torque converters to go bad, pump? input shaft bearing? Not sure where to go from here, other than a complete tear down.
 
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