Odd sound coming from tranny hump

So I sled pulled over the weekend. 3 passes. Everything seemed fine. I got on the highway this morning and merged with traffic, as I was doing so (3/4 throttle) I heard a sound that almost sounded like a buzzing/rattling coming from the passenger side tranny hump.

Everything was and still is acting fine, nothing out of the ordinary.

I let out of the throttle and it went away. So far with my experiments it only happens when I use 3/4 to full throttle from a stop after 50mph (as in merging with traffic) and when I'm in 5th with the convertor locked and rolling 70+ and I mash the throttle past 3/4.

The sound only happens when I'm in the throttle hard, if I'm just cruising it doesn't happen. And it still acts normal even when the sound is happeneing.


I'm just not sure what it could be. I have a sound clip but I can't upload it. I can send it via text. May have to make a YouTube account. I'm just looking for ideas what this may could be. I changed the oil and fuel filters 1500 miles ago. The tranny fluid is a nice red color, smells slightly burnt, but does have some solid material on the tip.

I could definitely be wrong but it could be where you are paranoid about it messing something up during the sled pull. That's Always how it is after doing something that you know is abusing the truck. You always notice little things that you didn't before. Hope it's nothing!

bft blue oval boys said:

I could definitely be wrong but it could be where you are paranoid about it messing something up during the sled pull. That's Always how it is after doing something that you know is abusing the truck. You always notice little things that you didn't before. Hope it's nothing!

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I'll text you the video. You tell me if it's "nothing"

JrStroker said:

I'll text you the video. You tell me if it's "nothing"

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Ok

bft blue oval boys said:

Ok

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It's "nothing" right? Hahaha

There is no way that it's not nothing cause that nothing definitely sounds like a big something.... lol

Pass side of trans hump? Check and see if the exhaust is contacting the cross member. I know when I get on it my trucks frame twists a little. Or it could be the certain harmonics of 3/4 throttle that is causing the vibration through the cross member from the exhaust

I sold you that dpf sensor if you still have my number you can send me the video

Stroked777 said:

Pass side of trans hump? Check and see if the exhaust is contacting the cross member. I know when I get on it my trucks frame twists a little. Or it could be the certain harmonics of 3/4 throttle that is causing the vibration through the cross member from the exhaust

I sold you that dpf sensor if you still have my number you can send me the video

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I'll check the exhaust before I leave work today.

Stroked777 said:

if you still have my number you can send me the video

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If anyone wants to hear the video thinking it will help, text me. 865.228.8073

I checked the exhaust. I'm pretty sure it's not touching anything.

JrStroker said:

I checked the exhaust. I'm pretty sure it's not touching anything.

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Check how much motion the exhaust has. Try to shake it. The motor shifts pretty good. That's where the exhaust is routed. Start there.

You have an iPhone?

Okay guys. It's definitely not the exhaust. I stopped by my mechanics and we drove it up and down the road and it's definitely somewhere in the tranny area. Thing was making all sorts of racket. It would do it at 3500 rpm 3rd gear under hard throttle only, in 5th tq unlocked at around 2500 rpm under hard throttle, then at 1800rpm in 5th tq locked hard throttle. Only do it under hard throttle. My mechanic thinks it may be the torque converter coming apart.
Told me to drop my pan and see what all is in there.

Does it sound like rocks in a can?

Kinda, but not exactly.

Hi I'm willing to bet it is the flex plate from what you describe. It's rare in an automatic transmission but it does happen. Especially in high torque applications and when pulling. Only makes loud rattling noise at certain sweet spots in RPM, speed or throttle pressure.
I had one go out on my in my SRT-10 Ram while towing a corvette home from Tennessee. When I got home took it to the transmission shop and it was the flex plate. Part is cheap the repair is time consuming/expensive. $800 later was all better.

This explains it best...skip to 40 seconds http://www.youtube.com/watch?v=qmuDtGZxuDc

Hope this helps!

certainly could be the flexplate

im gonna say converter. it has a tin sounding rattle when its smoked.

bigrpowr said:

im gonna say converter. it has a tin sounding rattle when its smoked.

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I say converter... She's gonna go out soon bud...

That or check downpipe to uppipe contact!

ramonpowerstroker said:

I say converter... She's gonna go out soon bud...

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bigrpowr said:

im gonna say converter. it has a tin sounding rattle when its smoked.

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ghohouston said:

certainly could be the flexplate

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rrod said:

Hi I'm willing to bet it is the flex plate from what you describe. It's rare in an automatic transmission but it does happen. Especially in high torque applications and when pulling. Only makes loud rattling noise at certain sweet spots in RPM, speed or throttle pressure.
I had one go out on my in my SRT-10 Ram while towing a corvette home from Tennessee. When I got home took it to the transmission shop and it was the flex plate. Part is cheap the repair is time consuming/expensive. $800 later was all better.

This explains it best...skip to 40 seconds http://www.youtube.com/watch?v=qmuDtGZxuDc

Hope this helps!

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So we are saying flex plate and/or convertor. On my dash daq, I monitor convertor slip, and it only shows a 10 at most while at WOT. Even if the sound is there, it still doesn't jump over 10.