Clunking noise from ring and pinion

[inyadreems]

I recently did my rear suspension all J&M street poly non-adjustable and developed a "clunking noise". All J&M directions were precisely followed. The pinion angle was within spec and the rear centered to Ford specs. (Note the car is NOT lowered, stock wheels and tires and stock suspension, we reused the original bolts, anti-clunking bushings and lubed all parts very well). The wheel hop is gone and the car takes off nice and straight while spinning but I developed a clunking noise coming from the rear when on and off the gas while in gear and sometimes over bumps.

I took my car back to the dealer and the tech went over every bolt re-torqueing them to specs, but the noise is still there. Nothing seems loose; there are no scorch marks on any of the suspension parts that would indicate movement. With the car on the lift and the tech underneath you can hear the noise inside the car when engaging the clutch/gears, but you don't hear it underneath the car. The noise gets louder when the back seat is removed but the UCA mount bolt is torqued and tight. I drove the car with the backseat out and the tech in the passenger seat holding the bolt underneath the seat and there is no movement or play from the bolt. We also lightly used a pry bar on the suspension parts and no noise or movement.

Today we found the culprit. When u turn the drive shaft manually left and right it makes a "clunking noise". Took the diff cover off and no metal shavings at all, gears look perfect, lash was within Ford spec (12,000), clutch paks and spider gears look good. The pinion angle was checked and it was within Ford spec also (-2). Put the cover back and refilled with RP and friction modifier. All work has been performed by an SVT mechanic.

Any idea what it could be? Could it be the pinion angle?

Thanx

 

[Alloy Snake]

Same problem here,Hopefully there is a solution.

 

[Juxtapositron]

Take it in to ford... there's lots of weird sounds that the rear can make due to a ring/pinion problem. They are currently replacing/fixing mine (and going some tranny work, I have the 1-2 powershift issue as well).

Mine is a 2012. Best of luck.

 

[inyadreems]

Take it in to ford... there's lots of weird sounds that the rear can make due to a ring/pinion problem. They are currently replacing/fixing mine (and going some tranny work, I have the 1-2 powershift issue as well).

Mine is a 2012. Best of luck.

Been to Ford 3 times and have a good relationship with the dealership.

 

[jimh]

There is going to be play in the rear, the trans and some noise from the coupler between the drive shafts. The new arms and bushings are just transmitting that noise better. You best bet, if the noise gets to you, is put some dynomat down under the back seat and over the upper control arm bracket. I think the noise is probably normal. Every performance or heavy duty vehicle I've been in has had some kind of drivetrain noise.
The factory soft rubber bushings hide it but you lose performance because of it. The new arms and bushings privide better performance and structural integrity but you lose noise cancellation. There's always a trade off.

 

[inyadreems]

There is going to be play in the rear, the trans and some noise from the coupler between the drive shafts. The new arms and bushings are just transmitting that noise better. You best bet, if the noise gets to you, is put some dynomat down under the back seat and over the upper control arm bracket. I think the noise is probably normal. Every performance or heavy duty vehicle I've been in has had some kind of drivetrain noise.
The factory soft rubber bushings hide it but you lose performance because of it. The new arms and bushings privide better performance and structural integrity but you lose noise cancellation. There's always a trade off.

I think your right. Check out this video I made. The e brake is on and the car is in first gear, while letting the clutch out slowly until it almost stalls. I don't see any movement in the UCA front or rear bushings. The creaking noise you hear is the E brake. Although, you don't hear the noise in the video I can hear it inside the car.

‪UCA‬‏ - YouTube

 

[jimh]

I think your right. Check out this video I made. The e brake is on and the car is in first gear, while letting the clutch out slowly until it almost stalls. I don't see any movement in the UCA front or rear bushings. The creaking noise you hear is the E brake. Although, you don't hear the noise in the video I can hear it inside the car.

‪UCA‬‏ - YouTube

I don't think it's your control arm clunking. To make sure you need to go back and forth between reverse and first in the test you did. Once the suspension is loaded in one direction it's not going to unload enough to move back to the other side of the bolt. Those bolts are pretty tight.
I think what you're hearing is normal drivetrain play and you don't have anything to worry about. Put some sound deadening material in if it starts to really annoy you. It's like transmission noise, yes helically cut gears are quieter than straighter cut gears but they aren't as strong.

 

[inyadreems]

In hindsight I probably should have went with the Roush Wheel Hop Reduction Kit, Adjustable pan hard bar and stock LCA's for a street car.

I can't find any complaints about the Roush WHRK and no increased NVH.

 

[jimh]

I have the J&M upper and lowers. I have no complaints. I can only hear the noise with the windows up and the radio on low. (I usually drive around with the windows open) I had an 03 cobra with a stock suspension and remember hearing the same noises. In my opinion the J&M pieces are superior.

$.02
jim

 

[inyadreems]

I have the J&M upper and lowers. I have no complaints. I can only hear the noise with the windows up and the radio on low. (I usually drive around with the windows open) I had an 03 cobra with a stock suspension and remember hearing the same noises. In my opinion the J&M pieces are superior.

$.02
jim

Thanx Jim

 

[03 DSG Snake]

I got a clunk in mine when doing the 3.73s and the Steeda upper w/bracket. Can get annoying, but I'm used to making noise. Everything FEELS good though, so the tradeoff is worth it.

 

[inyadreems]

What do you guys think about going to a 1 piece Dynotech aluminum driveshaft? Would that pick up the slop in the drive train?

 

[03 DSG Snake]

What do you guys think about going to a 1 piece Dynotech aluminum driveshaft? Would that pick up the slop in the drive train?

I think it would make the clunk worse, as the stock 2 piece has the tendency to 'soak' up some of the noise.

 

[Robertt305]

The nature of the S197 body is to creak clunk groan and make noises. Which increases when you upgrade your bushings or D/S.

Just get used to it or dynamat the crap out of your car...