Rear Diff Clunk

[Jeffs2006EvoIX]

Hey Fellow Evo Drivers, I know this is an old subject but want some advice. I had this clunk sound for a long time, installed my Beatrush Front Tranny Mount and it was gone. Recently I had the Stage II T/C Build done by Shep Trans, and now under hard acceleration it clunks everytime. I know the T/C is re shimmed to eliminate the slack, but since my car is a DD I don't want to replace the Mustache Bar or eliminate it either because my kids sit back there and don't want them to hear a constant humming you know? So is my only option the Energy Suspension Mustache Bar Bushings? Does anyone have these installed? Did it help? Does this Clunk from the Rear Diff actually hurt anything? or is it just an annoying noise?

Thanks for your time everyone......

[boostinbyyou]

diff slap....is the sound

but a bad humming sound, you might wanna check for fluid....

[Jeffs2006EvoIX]

My car doesn't have a bad humming sound, I must have worded it wrong, if I replace my stock Mustache Bar with a Mustache Bar eilimate kit, or replacement bar that doesnt use bushings and is a direct bolt on like this...Dif to cradle to frame, with no bushings, this set up would be great for a race car but not for a DD you would hear humming/vibrations into the rear of the car through the chassis. I don't want that since I have kids in the back. So Im looking for a different route..I think the Replacement bushings are my only choice that I know of.

[evopaul]

I have owned my evo 9 ,since she was new..My rear end has always clunked under hard shifting.At first i thought i broke my differential.To find out later on That it is normal on all CT9A's ...and i have driven several
I call it axle wrap!!!

[Jeffs2006EvoIX]

Has anyone found out if its harmful? I can live with the noise if it doesn't mess anything up. I think the bushings will help. Prior to the T/C Build the Front motor mount upgrade got rid of it completely. My Evo 8 I don't recall ever doing it, but then it didn't put out the power that my 9 is either. My 8 was bone stock. My 9 well isn't. haha. As long as nothing will break or get damaged by that clunk I am cool........but the bushings may be a cheap investment at $60.

[evopaul]

I have 17,000 hard miles Some times i fell like I'm going to rip the shifter from the floor board and my left foots going to to threw the floor board......not on problem.Like i said all of my friends EVO's do this as well.only when you shift hard.
I wouldn't loose sleep over it!

[phoreal]

try buying the beatrush rear diff bushings theyre stiffer then stock and eliminate alot of that clunk noise

[lg_4g]

+1 on the beatrush bushings. They took me 20 min to install and have eliminated the clunk completely.

You will hear a mild humming noise when you accelerate on the freeway though. Nothing too bad.

[Jeffs2006EvoIX]

Only 20 minutes to put in? Dont you have to lower the rear sub frame to do it? I found the Energy Suspension bushings are less expensive than the Beatrush bushings and I am sure are as good. 20 minutes though? I looked under there, seems like it would take a while to do. Looks like you have to lower the subfrome, unbolt the mustache bar drop it, push out the bushings, put in the new ones then bolt it back up. Do the OEM bushings come out that easily that you don't have to take the bar completely off to do the job? I noticed though the ES kit shows 4 bushings, while the Beatrush I thought showed 8? WTF?

[enVmyIX]

try buying the beatrush rear diff bushings theyre stiffer then stock and eliminate alot of that clunk noise


so you're saying that these bushings will drastically reduce diff slap under hard/fast shifting? Very intersting... i hear it slap every now and then when i let go (dump) the clutch too quickly when accelerating fast.

[phoreal]

they reduce it alot but not completely eliminate the cluck from dumping the clutch

[enVmyIX]

very cool, one more noob question: the slap/clunk - does it come from inside the diff? I have a feeling that it doesnt so then where is it coming from?

[phoreal]

i think its when the diff bottoms out on the rear diff carrier from what i was told

[cmj]

Those rear diff bushings work great. My cousins car had the Whiteline version, the cluck was almost completely gone.

[Jeffs2006EvoIX]

Im just curious on how its done in 20 mins. I am sure you have to pull the mustache bar, pop out old stuff put in new? or? Does anyone have pics when they did it? I would like to do it myself if I can. I can't be that hard. The ES bushings are almost 1/2 the cost of the whiteline set. Keep that in mind. I am sure they are equal in performance.

[UgmWRX]

Ive found shifting too quickly may cause this. I would just be careful with that if you don't want to adjust the car at all, just adjust your driving habit.

[EvoVIIIGSR]

Doesn't AMS carry a bracket as well that is supposed to aide in reducing diff slap as well?

http://www.amsperformance.com/cart/AMS-Mitsubishi-Lancer-Evolution-Evo-7-8-9-Moustache-Bar-Eliminator-Amsperformance.com.html

[Jeffs2006EvoIX]

AMS and Buschur sell mustache bars that will eliminate the slap, but thats great for a race car, not a DD. Allot of vibrations make it to the back seat with those. So, for practical DD Duty the bushings would be the best bet. BUT I feel they take more than 20 minutes to install. Depends on the kit I suppose. ES has a kit that includes 2 bushings, Whiteline has 4 and Beatrush has like 6-8, so I don't get it? haha. I will just get a kit from someone and install it. Mine slaps allot now. Any quick shift at all it makes noise. Thats WITH a solid front engine mount. Its hard to get a smooth shift on my 6spd. Maybe my clutch pedal needs adjustment. Who knows.

[HMatt]

^it's hard to get s smooth shift on your 6-speed? Dude, something is wrong.

[Jeffs2006EvoIX]

Its not that my car "clunks" all the time, its just if you don't shift "just" right it does it. I can imagine after hundreds of dyno runs, 120+F summer hear and all where I live?? The bushings are probably shot. Just rubber bits. The Poly I am sure would really help me. Just pan handling on the street right now to get money to buy them. Hey Im a State Worker, that is what I have to resort to. Thanks Schwarzenegger!!! Your a real CHUM O0

[littlejap33]

http://www.amsperformance.com/cart/AMS-Mitsubishi-Lancer-Evolution-Evo-7-8-9-Moustache-Bar-Eliminator.html


you need this hahah

[boostin619]

they all do it... ive owned 2 evo's and both did it

[crand002]

I installed the the Buschur Mustache Bar, problem solved.

[phoreal]

O0

[HMatt]

Does anybody else make an aftermarket mustache bar other than Bushur?

[one4]

ams and bushur... energy has bushing sets but that it i think

[HMatt]

AMS has the eliminator. I don't want that, too much noise carrys through. I'll probably end up going with the bushings.

[Jeffs2006EvoIX]

+1 on the beatrush bushings. They took me 20 min to install and have eliminated the clunk completely.

You will hear a mild humming noise when you accelerate on the freeway though. Nothing too bad.


Did you do this on a lift or something? I am really trying to comprehend how you replaced all those bushings in 20 mins. Most shops charge 2 hrs labor, and if I did it myself, I could see it taking several hours. Did you have help? a Lift? How did you press out the bushings too? Don't some of them have to be pressed out? The new ones pressed in? Just curious. 20 mins just seems crazy fast to me. Want to do mine?? haha.

[phoreal]

No just jack up the rear of the car n do it. The new bushings are solid metal IIRC the old ones should pop right put depending on the crustyness. Bolt everything back up n ur good to go O0


As far as a upgraded mustach bar it actually doesnt transfer all the noise youd think.