Howl from Rear End?

[FiveSpeed]

When I lowered the car I installed Steeda's "Stop the Hop" pack which included rear lower control arms and a tubular upper 3rd link. Since then the car has a howl between 60-65 mph and around 80-85 mph. In between or any other MPH there is no howl at all. The Steeda's upper arm is slightly shorter than the factory one and their website indicates it's a replacement of the factory upper arm and there should be no issues. I was worried there would be too much of an angle on the diff but once the car is on the ground it's straightened out like it should.

Any help would be appreciated! :shrug:

 

[01bluesnake]

Your more likely just hearing the noise transfer from the rear end due to the stiffer bushings used in the arms. Thats the purpose of the stop the hop kit, takes all the soft bushings out to stop play. It's not a bad idea to check pinion angle, but more likely to get a vibration at speeds when out of spec.

 

[grnenvy]

I have talked about this so many times your just another person with the same problem. I have tried multiple diff suspension parts and there all noisey. It's the bushings in the control arms not your pinion angle. 80% of the noise is coming from the upper control arm. I had to remove my Steeda adj the whine/hum drove me crazy. There will be a ton of people that respond telling u they don't have noise there crazy or deff. Most of the guys are young and don't care about a little noise or they have crazy loud exhaust and can't hear it.
IMOP u don't pay 40k for a car to make it sound like shit.
If I was u I would pull all that garbage off the car and just install a set of BMR lower control arm brackets with the factory stuff.
I get Zero wheel hop.

 

[sncbluegt]

I have talked about this so many times your just another person with the same problem. I have tried multiple diff suspension parts and there all noisey. It's the bushings in the control arms not your pinion angle. 80% of the noise is coming from the upper control arm. I had to remove my Steeda adj the whine/hum drove me crazy. There will be a ton of people that respond telling u they don't have noise there crazy or deff. Most of the guys are young and don't care about a little noise or they have crazy loud exhaust and can't hear it.
IMOP u don't pay 40k for a car to make it sound like shit.
If I was u I would pull all that garbage off the car and just install a set of BMR lower control arm brackets with the factory stuff.
I get Zero wheel hop.

So ur using the factory arms and bushings with just the addition of the brackets?

 

[S197OnSpray]

I have talked about this so many times your just another person with the same problem. I have tried multiple diff suspension parts and there all noisey. It's the bushings in the control arms not your pinion angle. 80% of the noise is coming from the upper control arm. I had to remove my Steeda adj the whine/hum drove me crazy. There will be a ton of people that respond telling u they don't have noise there crazy or deff. Most of the guys are young and don't care about a little noise or they have crazy loud exhaust and can't hear it.
IMOP u don't pay 40k for a car to make it sound like shit.
If I was u I would pull all that garbage off the car and just install a set of BMR lower control arm brackets with the factory stuff.
I get Zero wheel hop.

^This

I went through the same thing. Most of the noise is going to come from the upper control arm when swapped out for a poly, delrin or rotojoint bushing. Mostly due to the fact that the upper arm is connected to the cabin of the vehicle. You have a few options like lowering the car and adding relocation brackets depending on how low you go. You can also check out the Roush upper and lower arms as they utilize the GT500 style stiffened rubber bushings that do not transmit any NVH. Roush even has an upper arm and mount for 1" lowered vehicles as well.

 

[FiveSpeed]

I appreciate the quick replies. I just wanted assurance as to where the noise is coming from. It is also reassuring that others are having the same annoyance. I still find it odd how it only happens at certain speeds and then it magically goes away.

Thanks again guys!

 

[grnenvy]

I went to the Bradenton meet a couple months ago and I saw the Roush arms there beautiful. They use a stiffer stock stlye bushing that should be NVH free.
After trying a couple diff brands of rear suspension I'm finished.
Keep us posted if u buy the Roush arms.

Yes factory upper with Shelby lowers and BMR Brackets. Zero hop.

 

[mikestoyz]

I went to the Bradenton meet a couple months ago and I saw the Roush arms there beautiful. They use a stiffer stock stlye bushing that should be NVH free.
After trying a couple diff brands of rear suspension I'm finished.
Keep us posted if u buy the Roush arms.

Yes factory upper with Shelby lowers and BMR Brackets. Zero hop.

What springs?

 

[5lho]

I've got a tiny light hum from my 3.73s at that same speed. I have a Roush upper so very little NVH. It was there before but, the whining from the MT82 committing seppuku drowned it out. Now that Ford's fixed that, the hum is more noticeable. Normally I just speed up/slow down a bit. I'm hoping my coming GT500s will help :rolling:

 

[grnenvy]

Steeda Sport Springs and Adj Koni's. The direct replacement Koni's which are nice because u get to use your factory plates which keep the noise down. Aftermarket plates transmit noise.
I have had many mustangs and I told myself with this one I'm not going to ruin it with bad suspension choice's, Wheels,or go fast parts.
I don't like rattle's or squeeks.