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Roush UCA and NVH

8K views 19 replies 14 participants last post by  BLK 5.0 
#1 ·
I have a 2012 GT with Steeda sports amd Koni yellows, stock LCAs. I installed a Steeda adjustable UCA and HD mount to be able to adjust pinion angle. Part of the reason for choosing the Steeda was that they claim no increase in NVH. Despite their claim, I figured there would be some increase in NVH - it only seems to reasonable with the poly bushing.

The slight increase in road noise and small thumps over expansion joints and small bumps were aceptable to me. Despite several pinion angle adjustments, however, I still get what sounds like gear whine at about 40 to 50 mph and louder whine at 80 mph. It's too annoying for me and the wife.

I took the car to the dealer to have the rear end checked and took the technician with me on a demonstration drive. He heard the noise and agreed to check it out. The conclusion was that the rear end was fine and that the poly bushing on the UCA was transmitting vibration to the body. I trust the dealership and take them at their word.

I need to get rid of the noise but would still like to have a UCA that is a little better than the stock UCA. My questions are twofold: 1. change back to stock or try a roush UCA with their rubber bushing? 2. for owners with the Roush UCA, is it as quiet as the stock UCA?

Yes, the Steeda was installed and torqued properly.
 
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#2 ·
2. for owners with the Roush UCA, is it as quiet as the stock UCA?


The Roush UCA is as quiet as stock. I can say the same for all the rear suspension mods in my signature.
 
#3 ·
I had the UPR UCA and I did not like it. Switched to the Roush UCA and I have no complaints very quiet, car is lowered now with no issues.
 
#4 ·
Honestly I have no clue how to fix the issue however, you might want to try Dynamat, B-quiet Ultimate, or Peel and Stick in your trunk for some noise dampening if you can't resolve the issue.

Quick question is how much did you lower your car? because your pinion angle might be so slightly off that it doesn't even matter.

I know my pinion angle was darn near spot o after i lowered 1.25 rear and 1 front
 
#6 ·
While I am at changing the axle assembly with SVT 3.73, I will also install CHE Relocation brackets with UPR billet non adjustable lower control arms.

I am now also considering new UCA with or maybe without the chassis mount. It is really not easy to choose the best one as the internet is full of contradicting comments on different brands regarding NVH noise, pinion angle etc.

Is Roush UCA worth upgrading to at all? It seems to be just a beefed up factory UCA. What about BMR, Metco, Whiteline etc?
 
#7 ·
Well this kind of bums me out - I've got a Steeda UCA and mount ready to go on the car when I have some free time.

I did a lot of research and found the Roush was the quietest, I went with the adjustable so i could do a driveshaft or lower at some point.

Here goes nothing!!
 
#9 ·
It has been known that the 3.73's can have more whine. I have 3.55's and it is the same noise level as the stock uca. I still get the lash noise from the two piece drive shaft.
 
#10 ·
It has been known that the 3.73's can have more whine. I have 3.55's and it is the same noise level as the stock uca. I still get the lash noise from the two piece drive shaft.
thats one of the reasons why i never wanted to just swap the gears. I am hoping that the factory assembled SVT axle with 3.73 gears installed at the factory wont have any whine from the gear itself.

i've heard a lot of positive feedback for whiteline. I think i am gonna give their UCA/mount a try.
 
#11 ·
I disagree about 3:73 being naturally noisy, I had a 2010 gt with 3:73 they were as quiet as my 3:31's.....also if your gears are noisy you can change your gear oil over to amsoil gear oil, which quiets things down a bit...
 
#14 ·
I believe that its only some of the 3.73's are more prone to whine. The set up maybe more sensitive due to the crown gear moving at a faster rate at a given speed.
 
#12 ·
I'm sorry that you are experiencing noise with your setup, I do feel certain about the cause...


Our poly bushings (and any poly bushing) will transmit more NVH than the stock rubber ones, but if installed properly they do not MAKE noise. The dealer is telling you it is the bushing because you are hearing gear noise that was already present but more of it is being transmitted. Why would the dealer blame the bushing? Because they do not want to replace the gears for free. In every single case of this I have come across the noise has been in the gear set and the solution is there as well, or you can go to a softer bushing, but that does not address the problem, just quiets the noise that is there whether you hear it or not. Some dealers replace the gear set and correct the problem, some try to find a way out of it, but the noise is from the pinion depth and preload not being correct.
 
#13 ·
the noise is from the pinion depth and preload not being correct.

I think I know the answer here but is there any way to check this without taking the rear end apart? I will know soon enough I guess as my UCA is going in next week.
 
#16 ·
Old thread I know but I just got around to driving my car. It rides great and feels and sounds just like stock except for 60-80 mph, I get a pretty obvious whine. It is not so much the volume that's annoying but the tone - you can hear it even over a loud radio.

It's not horrible but not stock levels, and that is where I cruise most. My wife thinks I am crazy and she's right :gringreen

Steeda recommends friction additive in the rear end, also some Dynamat.

Has anyone come up with a solution here? I plan to try both but may end up selling this one for a Roush.
 
#17 ·
Gear noise is an install issue and yeah, they have it from the factory and it affects steep ratios more often. Ford's slap-to-torque assembly method is the problem here. It's been an issue since the '80s and Ford doesn't want to pay for more careful setup on the few steep gearset rears it sells.

I have Roush and it's as quiet as stock. it is a complete redesign over the stock mount, you'll see that when they are side by each. I get the same noise roughly in that same speed range, only noticeable since installing the Poly LCAs. It's not loud enough to make me pull down the rear and change the gears though, that's for sure.
 
#18 ·
My car is running 3.73 gears and Ford Racing P Springs. I originally tried the Steeda UCA but it transmitted a little more driveline noise into the car. My main complaint was the driveshaft clunking and not more gear noise.

I switched over to the Roush UCA and it is comparable to stock in terms of NVH. Still a minor clunk every now and then but very liveable. The quality of the arm is OEM and provides no pinion adjustment.

I will add that the Steeda UCA is a high quality piece and I may give it another try if I decide to buy a 1 piece driveshaft. It is just beefier and gives you the ability to adjust pinion angle.
 
#19 ·
The issue is your rear end. Ford already replaced my pumpkin, DS, and trans output bearing at 10K miles. Mine is making unbearable noise again and due to my mods - similar to yours, they are refusing to do the work. My diff was full of metal shavings...I have a 14 track pack with the 373s, as well.
 
#20 ·
I have Roush UCA along with Spohn poly/delrin adjustable lower control arms and 3.73's and get no extra NVH. I agree with others that the gears are not optimally set.
 
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