Powerflex purple diff bushes - replace rear only?

Il y a plusieurs fils sur les buissons poly pour le diff et ceux que j'ai lus ont beaucoup de questions non répondues.

J'étais déchiré entre les buissons powerflex noirs (95A) ou violets (80A) pour le diff. Pour la sensibilisation, je change les buissons de sous-cadre arrière à l'allié TMS.

J'ai opté pour le violet parce que je ne veux pas de diff wyne et certains propriétaires ont mentionné une petite augmentation avec la série noire. Si quelqu'un a des vidéos avec la série noire diff buissons pls post.

Questions
1 - est-ce que quelqu'un exécute les buissons de diff pourpre et y a-t-il une augmentation dans le gémissement de diff?

2 - étant donné que la douille arrière est en mousse et les 2 autres en caoutchouc plus dur. Est-il nécessaire de remplacer plus que le buisson en mousse?

3 - Si quelqu'un a installé l'amortisseur de diff de Malek (MRF), s'il a résolu le problème avec des buissons solides / delrin diff?

Merci.

Je viens d'acheter AKG rouge pour la sous-trame et noir pour le diff. 410 $ expédiés de Pelican. Pas encore dans la voiture donc pas de feedback. Sur la base des commentaires sur diff whine, je suis allé avec noir au lieu de rouge pour le diff. C'est censé être ma voiture confortable.

J'avais les deux douilles de sous-trame solides TMS + douille diff powerflex (violet). J'ai remplacé les 3 bagues diff avec le travail de sous-trame.

Il a un peu gémir de la diff maintenant - tout est venu du buisson Diff. Le niveau sonore du sifflement dépend en quelque sorte de votre régime, vitesse et degré d'accélérateur. Pour moi, ce n'est pas trop fort et la plupart du temps le gémissement est couvert par mon échappement Akra. Personnalité J'aime le son de diff wyne.

testdriver a écrit

J'avais les deux douilles de sous-trame solides TMS + douille diff powerflex (violet). J'ai remplacé les 3 bagues diff avec le travail de sous-trame.

Il a un peu gémir de la diff maintenant - tout est venu du buisson Diff. Le niveau sonore du sifflement dépend en quelque sorte de votre régime, vitesse et degré d'accélérateur. Pour moi, ce n'est pas trop fort et la plupart du temps le gémissement est couvert par mon échappement Akra. Personnalité J'aime le son de diff wyne.

Hmmm, je ne m'attendais pas à ce que les pourpres produisent des diff whines - Damm!

Un autre membre du forum m'a envoyé un message alors qu'il courait les buissons de diff série noire et a dit il y avait gémir à régime constant aux vitesses autoroute / autoroute mais c'était juste perceptible. Son partenaire ne l'a même pas remarqué.

tes-vous capable de poster une vidéo avec le whine pls?

pbonsalb wrote

I just bought AKG red for the subframe and black for the diff. $410 shipped from Pelican. Not in the car yet so no feedback. Based on comments about diff whine, I went with black instead of red for the diff. This is supposed to be my comfortable car.

Your feedback on the powerflex black would be appreciated.

When do you expect to get the install done?

Probably in a month. Just need a free weekend.

I installed the purple diff bushings and solid aluminum subframe bushings. I only hear the diff whine from 55-60 mph. I do have an Akrapovic Evo exhaust that most likely masks some of the whine.

burnrbr wrote

I installed the purple diff bushings and solid aluminum subframe bushings. I only hear the diff whine from 55-60 mph. I do have an Akrapovic Evo exhaust that most likely masks some of the whine.

Hi. Did you install all 3 bushes? So the diff whine range is very narrow. Is your car manual or DCT. I believe the whine is more pronounced with DCT cars. My stock car has a little diff whine at certain speeds, most people would not notice. My previous manual car did not.

Ant Man wrote

Hi. Did you install all 3 bushes? So the diff whine range is very narrow. Is your car manual or DCT. I believe the whine is more pronounced with DCT cars. My stock car has a little diff whine at certain speeds, most people would not notice. My previous manual car did not.

I installed all three purple bushings. My car is a DCT and yes the noticeable whine is only 55-60 mph.

burnrbr wrote

I installed all three purple bushings. My car is a DCT and yes the noticeable whine is only 55-60 mph.

Do you think the poly diff bushings made a difference in addition to solid subframe bushings?

edwardgtxy wrote

Do you think the poly diff bushings made a difference in addition to solid subframe bushings?

If you're referencing the whine, I did both that the same time so I can't directly comment.

The research I've read on this forum indicates that if you don't won't any whine then only do one not both. If you want to protect your diff from broken bolts, then upgrade those bushings. If you want a more planted rear suspension and less wheel hop, then replace the sub frame bushings. Doing both sub frame and diff bushings will result in some whine being heard inside the car. If you do solid diff bushing and solid sub frame bushings you'll get a lot of whine all of the time. I went the route of the softer poly diff bushings to reduce the whine which was successful. I'm not supercharged, so the "basic" poly bushings are more than enough for my situation. I've seen stock M3 break their diff bolts and tear up their sub frame mounts. It's not a situation I want to be in. I choose the solid sub frame bushing for improved rear end feel that I've read about. I'm generally happy with my choices, but it would have been great to have no whine and all benefit.

Good thread!
Going with Solid + Powerflex Purple!

Do we really need a harder diff bushing with DCT??
I have yet to see broken diff bolts on a DCT car. Has this happened lately?
.

aus wrote

Do we really need a harder diff bushing with DCT??
I have yet to see broken diff bolts on a DCT car. Has this happened lately?
.

I think it's more that if you're already taking the subframe down to do the subframe bushings, that's the right time to also do the diff bushings.

I am planning on Solid + purple sometime down the road. DD + HPDE.

Anyone go yellow?

I have the MRF solid subframe bushings. I believe he used derlin diff bushings from turner. The whine is minimal, and can only be heard with the windows up.

What are these "softer poly bushings" some have mentioned? Are they talking about the purple ones or is there another brand?

Powerflex purple is probably the softest. I bought akg black but not installed yet.

pbonsalb wrote  

Powerflex purple is probably the softest. I bought akg black but not installed yet.

I did black as well, still a significant amount of noise.

I currently have solid aluminum subframe bushings. I previously had Delrin diff bushings but recently replaced them with PowerFlex purple diff bushings. I also have the differential damper that MRF recommends installed on the car, which was also on the car for some of the time I had the Delrin bushings.

I have a DCT car.

My thoughts are as follows:

1) The subframe bushings absolutely transform the rear end of the car, IMO. It is more noticeable the harder you drive and push the car.

2) For me, the Delrin differential bushings added a significant and noticeable amount of differential whine. It was most present when cruising on the highway. I found it annoying. I also noticed some knocking and clunking from the driveline when putting the car into reverse, neutral, or drive. I did not find this particularly annoying.

3) The differential damper took a bit of the whine out (maybe 10%), but resulted in a fairly significant (>50%) reduction in the knocking/clunking.

4) The switch to PowerFlex purple differential bushings reduced probably another 90-95% of the differential whine to the point where I honestly no longer hear it even with the windows up and the radio off. Maybe in that scenario, if you absolutely strain to listen for it, you might catch the faintest whine at the perfect speed for a quick moment. And even then, that would only be true if you knew what you were looking for, which 99% of you will not.

5) In terms of performance, I perceive almost no difference in performance between the Delrin and poly diff bushings. If there is, it is slight, maybe 10%. This leads me to believe that 90% of the improvement in the rear-end feel is from the subframe bushings and that the differential bushings are mostly icing on the cake.


TL;DR:

Solid aluminum subframe bushings paired with PowerFlex purple differential bushings give you at least 90% of the performance benefits of a full solid setup, but with no more than 10% of the noise associated with a full solid setup.

Hujan wrote  

I currently have solid aluminum subframe bushings. I previously had Delrin diff bushings but recently replaced them with PowerFlex purple diff bushings. I also have the differential damper that MRF recommends installed on the car, which was also on the car for some of the time I had the Delrin bushings.

I have a DCT car.

My thoughts are as follows:

1) The subframe bushings absolutely transform the rear end of the car, IMO. It is more noticeable the harder you drive and push the car.

2) For me, the Delrin differential bushings added a significant and noticeable amount of differential whine. It was most present when cruising on the highway. I found it annoying. I also noticed some knocking and clunking from the driveline when putting the car into reverse, neutral, or drive. I did not find this particularly annoying.

3) The differential damper took a bit of the whine out (maybe 10%), but resulted in a fairly significant (>50%) reduction in the knocking/clunking.

4) The switch to PowerFlex purple differential bushings reduced probably another 90-95% of the differential whine to the point where I honestly no longer hear it even with the windows up and the radio off. Maybe in that scenario, if you absolutely strain to listen for it, you might catch the faintest whine at the perfect speed for a quick moment. And even then, that would only be true if you knew what you were looking for, which 99% of you will not.

5) In terms of performance, I perceive almost no difference in performance between the Delrin and poly diff bushings. If there is, it is slight, maybe 10%. This leads me to believe that 90% of the improvement in the rear-end feel is from the subframe bushings and that the differential bushings are mostly icing on the cake.


TL;DR:

Solid aluminum subframe bushings paired with PowerFlex purple differential bushings give you at least 90% of the performance benefits of a full solid setup, but with no more than 10% of the noise associated with a full solid setup.

Hm. I may pull my AKG black and give the purples a whirl. Hopefully it gets rid of some of my whirl. See what I did there? Lol

Where can I find this diff damper? I did a search yielded no results. It's not the defiv diff brace correct?

Move Over wrote

Hm. I may pull my AKG black and give the purples a whirl. Hopefully it gets rid of some of my whirl. See what I did there? Lol

Where can I find this diff damper? I did a search yielded no results. It's not the defiv diff brace correct?

+1

What's the diff damper??

Are there PowerFlex poly rear sub-frame bushings available. If yes, has anyone compared them to aluminum?
Great info here.
.