Very loud gear whine after UCA install, is there any cure?

[john11gt]

I installed a Steeda UCA with the stock mount this weekend and when I took it for a drive afterwards I noticed some pretty bad gear whine between 60-80 mph. There is a faint whine below that speed but not real bad but at about 60 it gets loud, like you cant NOT hear it. Around 70 its still pretty loud but the tone changes and it doesnt seem as bad, at 80 it gets obnoxiously loud, I can have the music turned way up and still hear it.

The pinion angle is set to about 1-1.5 and there isnt any vibrations when Im driving, its just the really loud gear whine. I do have the trunk stripped and the back seats stay out of the car so Im sure thats not helping but its so loud I dont think it would make that much of a difference.

I was thinking about getting some rubber washers and putting them between the UCA mount and the body to absorb some of the vibrations, would this be a bad idea?

 

[bmyles]

Mine gets loud around 80 to but it's quiet as a mouse till then.

 

['14 Shelby]

I have the BMR UCA & LCA's & Relo brackets. I noticed the same after installation.

 

[SignalZero]

I installed a Steeda UCA with the stock mount this weekend and when I took it for a drive afterwards I noticed some pretty bad gear whine between 60-80 mph. There is a faint whine below that speed but not real bad but at about 60 it gets loud, like you cant NOT hear it. Around 70 its still pretty loud but the tone changes and it doesnt seem as bad, at 80 it gets obnoxiously loud, I can have the music turned way up and still hear it.

The pinion angle is set to about 1-1.5 and there isnt any vibrations when Im driving, its just the really loud gear whine. I do have the trunk stripped and the back seats stay out of the car so Im sure thats not helping but its so loud I dont think it would make that much of a difference.

I was thinking about getting some rubber washers and putting them between the UCA mount and the body to absorb some of the vibrations, would this be a bad idea?

Just wanna clarify, that's -1/1.5 degrees, right? Just wanna make sure, if it's positive, that could very well be your issues with being loud. My whole rear suspension now is BMR poly stuff and it's nowhere near loud. What gear?

 

[Coyote5o]

I have BMR upper and lower also - I hear a slight whine about 60mph and it gets pretty loud over 80. I had my ring n pinion replaced under warranty prior to this all for a whining rear but this doesn't seem as bad. My solution is lower windows, louder radio/exhaust . Comfort and performance don't go together well - I'll keep the performance

 

[bam2012@TBR]

OP, when you set pinion angle and tighten everything down did you have the car sitting on the tires or on stands? The car needs to have its full weight on the tires on all four corners to set pinion angle properly, this could be your issue if not. I dd my car with full heim joint control arms upper and lowers and I have very little if any gear whine at any speed.

My 12 had factory 3.73s and I could hear them a little more than the 3.31s I added, my 3.15 in my 14 are the quietest rear gear I have had yet.

 

[Nuar]

I would try to eliminate the whine with angle adjustments, and then what ever is left, use something like dynamat all over the area of the UCA mount on the inside of the car. (Basically under the rear seat)

 

[john11gt]

Yea the pinion angle was set to -1 - -1.5 with jack stands under the axles. I cant remember if I tightened everything down with the rear end compressed though, Im going to assume not, Wednesday I will loosen everything up and tighten it back down with the rear end jacked up and hope that makes a difference.

The gear in the car is a 3.73

Any opinions on using thing rubber washers between the mount and the body? I know it would allow the control arm to flex a small bit but I dont think it would be anywhere near as bad as the flex from the stock piece.

 

[blackbeast12]

Pinion angle adjustments must be made with the weight of the car on its wheels not axles on jackstands! Rubber bushings don't have the durometer strength to withstand the torque you will apply to the mounting bolts.... Your problem is your pinion angle is incorrect because you set it with the weight off the tires!

 

[john11gt]

The instructions included with the Steeda control arm said you can check pinion angle with the jack stands under the axles?

 

[Justin81]

I did a whole bunch of stuff to mine at one time. I lowered it 1.5, shocks/struts, Steeda Billet lowers with the Spherical Delran ends, upper adjustable control arm which I believe 1 side to be spherical also. I have 2 sounds that are a killer. 1 is an NVH road noise that sounds like the rear is in the back seat. To better explain it, it sounds like there are 20 AC vents blowing air at full blast at all times while driving. The radio covers that up but it still annoys me. The other is a high pitched gear whining sound while cruising. I didn't take notice of what RPM it occurs but my 4 year old daughter pointed it out to me on the way to AM car show this weekend. She said it was bothering her ears which is not really good for me. I would love to switch over this stuff to fully bushed parts but it's tough because this stuff really works. I have no wheel hop issues and the car hooks pretty well.

 

[slagburn]

Pinion angle is not going to make the gears whine.

The problem is the gears were noisy before, but dampened by the squishy stock uca bushings. Those are gone now so the noise becomes very evident.

 

[BornCoqui]

Pinion angle is not going to make the gears whine.

The problem is the gears were noisy before, but dampened by the squishy stock uca bushings. Those are gone now so the noise becomes very evident.

I agree, once I put mine in there was a lot more gear whine.

I'm also a 3.73 car

 

[Nuar]

I've read on multiple occasions where people had rear end noise, and once the pinion angle was tweaked, a lot of it was gone...
I haven't experienced it myself yet, so I can't be 100% certain of that, just sharing what I've seen people post about.

 

[greyhk2]

I wonder if switching from a UCA to a torque arm would get rid of the whine?

 

[86Fbody]

Pinion angle adjustments must be made with the weight of the car on its wheels not axles on jackstands! Rubber bushings don't have the durometer strength to withstand the torque you will apply to the mounting bolts.... Your problem is your pinion angle is incorrect because you set it with the weight off the tires!

Explain the difference between having the car resting on the tires and resting on the axle on jack stands. In my mind the springs and everything else would be compressed the same since the wheels are attached to the axles.

 

[BMR Tech]

I believe we also have that in our instructions.....but it is simply because it is easier for most people. Pinion angle is a guessing game, when it is all said and done...so..

To answer the above statement:

Explain the difference between having the car resting on the tires and resting on the axle on jack stands. In my mind the springs and everything else would be compressed the same since the wheels are attached to the axles.

There is absolutely a difference between having the car supported by the axle tubes....and having it supported by the tires. It is just how physics works.

You cannot duplicate accurate ride height, without having the car sitting on the tires.

If you put jack stands under the a-arms....and the axle tubes, you will have an extra 1"~ (even more) wheel gap, compared to setting the car on the tires.

I deal with this everyday. People install our lowering springs, and call me.

"I Put your lowering springs on my car and it didn't make a difference"

Is the car on jack stands?

"Yes"

Put the car on the ground, then call me back.

 

[Nuar]

So Kelly, would you say that a loud rear end noise could be because a slightly off pinion angle?

 

[BMR Tech]

Loud? I don't think so.

Pinion angle has a little to do with the noise (harmonics) being transferred into the cabin....but not as much as people seem to believe. Heck, I wish it was - I'd sell more adjustable UCA.

I mean, it does help for sure. I've dealt with very picky customers who I eventually got "fixed up" by making them content, with correcting pinion angle....but a slightly off PA will not cause "loud" noises. Something else is contributing.

Keep in mind, the joints on these (all) driveshafts have operating range limits that far exceed what most see, typically. You can (should be able to, by design) operate these joints at significant working angles, without excessive noises.

NOW - I will say, having a excessive amount of angle difference between the trans and the pinion.....AND having an aftermarket UCA, can definitely cause some louder than usual "whirring" as I see people call it. You can lessen the harmonics/whirring by running a smaller angle difference, with an adjustable UCA.

 

[BMR Tech]

For people who have troubles with pinion angle settings.....typically, setting the pinion flange angle to ZERO when the car is on a flat/level surface....will be close to where it should be. The driverain angles on these cars is almost always in the 2-3 degree down range.

If you have your car on a drive on lift....ramps, etc....and your pinion angle reading is outside of the -2 to +2 range...you may want to give me a call.