Whine on deceleration

[DSM4me44]

I don't remember having this noise before I had my clutch and flywheel replaced but it is hard to say, because it sat all winter before hand.

When letting off the gas or downshifting (engine breaking) the car makes a whining noise but drives fine.

What is the best way to pin point which part of the drive train this is coming from?

I have a new Fidanza 3.2 with Fidanza 8lb flywheel installed. I had a shop do it this time, so I do not know what fluid is in the transfer case, but there is Penzoil Syncromesh in the transmission.

 

[viprez586]

Completely normal.
<img src="http://www.dsmtuners.com/gallery/files/8/0/1/3/1/100_3984.jpg" alt="100 3984" />

See the yellow springs on the clutch disc on the right?
These springs are designed mainly for one purpose but actually have two.
The main purpose is to provide a smooth engagement of the clutch when starting out from a stop.

However, when your rolling in the gear and decide to de-accelerate these springs absorbs the crankshaft vibration.
Think about it. You went from a stock clutch - which has nice smooth & easy springs.
Now you have bad ass springs in there to take up all the slack.

Under Decel, in gear - the fuel is cut, the motor is not ideally under any kind of load so it's just kind of coasting letting the friction of the road slow it down. The manufacturer doesn't account for any type of drivetrain noise outside of OEM specs(/clutches), which is why you never heard it before.

In theory your hearing drivetrain "ringing" from the entire clutch assembly resting on the input shaft (splined to the clutch disc) "rocking" back and forth the pressure applied from the clutch disc springs and the force of the road slowing you down.

Tires -> Axles -> Transmission -> Entire clutch assy. -> rotating assy.

Make sense?

 

[innocenttalon]

samething my car have since I installed my fidanza FW and stage 5 Comp clutch.

 

[red_devil]

Swapping the the driveshaft support bushing to billet ones helped a little.

 

[AlaskanDsm]

or you could be like me and have a bad bearing on the inside of the tranny where the tranfer case connects... that makes a lot of whining noise but going on 10,000 miles and it hasn't gotten any worse... yet *knocks on wood*

 

[Imback]

you will get used to the findanza

 

[viprez586]

Swapping the the driveshaft support bushing to billet ones helped a little.

I was thinking about doing that but I can't find myself spending more money on this effing car!!

Plus I have 90A filled & rear welded motor mount so I'm use to shakes and noises.

 

[DSM4me44]

Transfer case was bad. Problem solved with a rebuild.

 

[tjbiker031]

Completely normal.
<img src="http://www.dsmtuners.com/gallery/files/8/0/1/3/1/100_3984.jpg" alt="100 3984" />

See the yellow springs on the clutch disc on the right?
These springs are designed mainly for one purpose but actually have two.
The main purpose is to provide a smooth engagement of the clutch when starting out from a stop.

However, when your rolling in the gear and decide to de-accelerate these springs absorbs the crankshaft vibration.
Think about it. You went from a stock clutch - which has nice smooth & easy springs.
Now you have bad ass springs in there to take up all the slack.

Under Decel, in gear - the fuel is cut, the motor is not ideally under any kind of load so it's just kind of coasting letting the friction of the road slow it down. The manufacturer doesn't account for any type of drivetrain noise outside of OEM specs(/clutches), which is why you never heard it before.

In theory your hearing drivetrain "ringing" from the entire clutch assembly resting on the input shaft (splined to the clutch disc) "rocking" back and forth the pressure applied from the clutch disc springs and the force of the road slowing you down.

Tires -> Axles -> Transmission -> Entire clutch assy. -> rotating assy.

Make sense?

Yes! Nice usage of my pic!!!

 

[AlaskanDsm]

I know this is an older thread but how did you identify that it was the transfer case that was bad?

 

[DSM4me44]

I called Shep racing and explained a few things to try. Eventually, I had the shop take apart the transfer case and it was obvious once you got it apart, because the gears were starting to shred.