Diagnosing Suspected Torque Convertor Sound

[Ifixyawata]

The vehicle is my wife's 2004 Mountaineer 4.6L. Noticed a metal, clanky rattling sound from the vicinity of the torque convertor when stopped, idling in any drive gear (D or R). It goes away when the vehicle is in motion, doesn't seem to occur when idling in park.

The sound is very 'external' what you might even think of as fan blades hitting something, but, again, only occurs when the vehicle is idling, stopped in Drive.

Does this sound like a broken fin on the torque convertor or something of that nature? I don't think this vehicle has an inspection panel under the torque convertor to check anything that way.

 

[ctechbob]

I don't think you could break a hard part inside a TC and not end up with almost instant catastrophic damage. I'd take a good hard look at the flexplate though.

 

[Ifixyawata]

I don't think you could break a hard part inside a TC and not end up with almost instant catastrophic damage. I'd take a good hard look at the flexplate though.

I wondered about that but whatever it is coincides with some jumpiness on rolling forward from a stop.

 

[ctechbob]

@clinebarger might know of more things to have a look at.

 

[clinebarger]

Internal Torque Converter issues will usually cause debris in the pan, Flexplate, Catalytic Converters, & Heat Shield's are far more common for making noise in that vicinity.

 

[wolfox03SS]

^^^ +1 on heat shield rattling around at idle.

More rare, check brake lines. They can rub and rattle at idle if they popped the plastic looms or run close against the frame/body.

 

[Ifixyawata]

Internal Torque Converter issues will usually cause debris in the pan, Flexplate, Catalytic Converters, & Heat Shield's are far more common for making noise in that vicinity.

Okay, I will give the heat shields etc another look. I know the manifold heat shields are pretty trashed on this vehicle so I guess the cat convertor ones could be too.

I don't think there's an inspection cover for the flex plate, how else would I determine if it has any cracks?

 

[Ifixyawata]

^^^ +1 on heat shield rattling around at idle.

More rare, check brake lines. They can rub and rattle at idle if they popped the plastic looms or run close against the frame/body.

I'll take a look at these items also. It's only an issue at idle under load, not in Park or Neutral.

 

[Ifixyawata]

I took a few videos of the sound today.

https://youtube.com/shorts/AwM5-xLP_s8?feature=share

https://youtube.com/shorts/XxbqCYEMfJU?feature=share


And I did find an inspection cover and got some sounds from there too. Didn't see any signs of other damage though.

https://youtube.com/shorts/YV158HS-y_A?feature=share

 

[Ifixyawata]

Seems pretty distinctly to me that the sound is coming from the torque convertor. I'm thinking the one more thing I can do to really check and confirm is drain a bit of fluid and see what the condition is and see if the is any debris present. Other than that I can't see any sure way to be positive that it's the torque convertor.

In the event that I get metal shavings, etc in the fluid, is there a chance that I can change out the TC, replace fluid and filters and be good to go again? The transmission still shifts fine as of the last time it was driven.

 

[wolfox03SS]

Or...or...

Just remove the accessory belt. If she is quiet after that, start looking at your water pump, power steering pump, alternator, ac compressor, idler and tensioner.

A bad bearing in a power steering pump in a friend's Focus from misaligned pulley made it sound like rubbish. Knock-a-knock-rattle all the way.

I found it after a beltless run and then spinning everything that looked like a pulley. In his case, that slightly misaligned power steering pulley side-loaded it into early death. The cure: replacement and laser aligning the PS pump.

I hope yours is only a worn belt or recently serviced accessory.