Need help with diff whine?

[Mog-10]

So I wanted to share my experience with trying to eliminate diff whine.

So originally I was running Turner solid diff mounts to help with broken diff bolts and Axel hop that had caused a lot of Carnage. The whine was bad and I lived with it for a year. I decided to do an super 8.8 swap it has a Torsen T2R differential and is known for being noisy even when using factory rubber mounts. I had mounted it solid with steel mounts no bushings at all. The whine was horrible.

So I had remembered an old dynamat display with the bell and had the idea of using something similar.

I decided to go with Rockville rockmat as it is cheap butyl rubber and has an adhesive that is good to 300° f . Cost less then $15

I had used two strips at the front of the sub frame and back at the top most part closest to the body. I had also stuck a chunk on the top of the diff.

Well it worked no more whine. I have been running it like this for about two months the adhesive is holding with no signs of delamination from the heat under the car.

I know my set up is different then everyone else but the concept should work the same. I hope this can help quiet some differentials.

Yes I know this stuff is made for car audio.

[Redd]

You, my friend, are a genius!

[Throatpunch]

That's a great idea!

[CTMike]

Giving this a small bump since I saw it referenced in a recent thread - anyone else taken a similar approach?

[RocketyMan]

I'm willing to try it out since I'm getting a whine at the rear at 45 mph...

[Gossypiboma]

My rear subframe is currently out for subframe and diff bushings. I'll give this a go. Two sheets of 12x12 seem to be plenty?

[amrazM]

Originally Posted by Gossypiboma

My rear subframe is currently out for subframe and diff bushings. I'll give this a go. Two sheets of 12x12 seem to be plenty?

two 3x6 strips did it for me.

[RocketyMan]

Originally Posted by amrazM

two 3x6 strips did it for me.

At the location on the rear-subframe like mentioned above?

[RocketyMan]

Here's the sound deadening location I did on mine. This was done WITHOUT lowering the subframe at all--not ideal, but not too difficult.

It's done at the sides where the upper big "tube" of subframe is done. Then on the back side (which the diff is covering because it's hidden).

I haven't tried it out yet, but we'll see if it helps!

[Mog-10]

That should work.

[kerrit]

bumping this, reduced my whine by about 75% - well worth it, did it while subframe on the car, a bit tight but only took about 10min.

I had whine completely stock years ago, then the poly 'street' diff bushings made it worse. Now it's livable.

[RocketyMan]

Originally Posted by kerrit

bumping this, reduced my whine by about 75% - well worth it, did it while subframe on the car, a bit tight but only took about 10min.

I had whine completely stock years ago, then the poly 'street' diff bushings made it worse. Now it's livable.

Nice! Thanks for reporting your results!

I would say mine helped too.

[Mog-10]

Bumping this for more too see.

[HairTooLongToo]

I recently tried this as my car has a pretty good case of the 43mph / 45mph diff whine. However I didn't notice any difference. Was worth a try though.

I used this exact product and applied 2 approx 3x6 strips to the center of the rear big subframe tube.

I might try doing some panels in the interior at some point, directly onto metal. Thinking maybe the trunk floor or even the left door where it seems to resonate from.

[RocketyMan]

Yeah I still hear mine at that exact speed of 43 mph to 45 ish. It def toned it down a bit, but I'm sure more strips on the subframe would help. I'm thinking the colder weather is causing the rubber butyl to not be as effective in cutting down the resonance/whine as oppose to when it's warmer.

[HairTooLongToo]

That's a promising theory about the cold temperatures and hope you're right. I'll find out once the car is back out after winter. Next time I have access, I'll try throwing strips onto the front subframe tube as well. I'll be quite happy even if it can dull the sound a bit.

[Mog-10]

Each tube of the subframe can resonate sound from the diff, so if you only do one or 2 of the 4 there is a chance of sound resonating.

[DrFerry]

In my case, I had other things going on with the diff bearings due to rebuild and LSD installation errors by the supplier. However, when I removed the solid diff bushings and went back to the OEM diff bushings most of the diff noise went away. Problem mostly solved.... Ultimately, the diff had to be rebuilt as well as the ring and pinion backlash reset by a local repair shop. Here's a link to that thread.
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HELP - Modulating Whirring Sound From Diff or Rear End Area???
https://www.m3post.com/forums/showthread.php?t=1540429
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