loud booming clunk on fast 1-2 shift - Page 2

Warrtalon · Apr 20, 2006, 11:13 AM

It's just the carrier bearing in the rear. The driveshaft is hitting against it, because the bushing is too soft. I used to think it was the rear diff, but it's not. Btw, it doesn't happen on a powershift, but it happens on a fast shift, or what I call a snap shift. Now that I can powershift the 1-2, it doesn't happen anymore, but it used to happen on every 1-2 drag shift in the past...

Russell K · Apr 20, 2006, 02:58 PM

Quote:

Originally Posted by Warrtalon

It's just the carrier bearing in the rear. The driveshaft is hitting against it, because the bushing is too soft. I used to think it was the rear diff, but it's not. Btw, it doesn't happen on a powershift, but it happens on a fast shift, or what I call a snap shift. Now that I can powershift the 1-2, it doesn't happen anymore, but it used to happen on every 1-2 drag shift in the past...

SO- What bushings need to be replaced in order to fix this? I am no dummy when it comes to this stuff, but for the life of me I cant remember what a carrier bearing is. Is that the part of the rear diff that attaches to the driveshaft? I have the Energy Suspension bushings for the rear diff, but have never installed them. I also just received the Laile propshaft bushings. I will attach Lailes' picture of the bushings to clarify. I get this clunk every now and then. I was hoping the Laile bushings would fix this. I guess what I am saying is I think that you are describing the propshaft bushings as the bushings that are too soft, which causes the noise during shifts.

dan628 · Apr 20, 2006, 03:12 PM

I found thins link on vivid racing, perhaps these would help?
Energy Suspension EVO8 Rear Differential Mount Bushing Set
http://ww2.vividracing.com/catalog/p...9ff1b3cfecff86

SuperHatch · Apr 20, 2006, 03:14 PM

Quote:

Originally Posted by Warrtalon

It's just the carrier bearing in the rear. The driveshaft is hitting against it, because the bushing is too soft. I used to think it was the rear diff, but it's not. Btw, it doesn't happen on a powershift, but it happens on a fast shift, or what I call a snap shift. Now that I can powershift the 1-2, it doesn't happen anymore, but it used to happen on every 1-2 drag shift in the past...

Funny, I used to think it was the rear bushings, and it was!

I replaced my rear diff bushings with Energy Suspension pieces, the clunk was gone and never came back. Also solved my wheelhop issue.

Ev0ikon · Apr 20, 2006, 04:12 PM

Quote:

Originally Posted by SuperHatch

Funny, I used to think it was the rear bushings, and it was!

I replaced my rear diff bushings with Energy Suspension pieces, the clunk was gone and never came back. Also solved my wheelhop issue.

Thanks. That sounds like an easy and effective fix

Wheelhaus · Apr 20, 2006, 07:32 PM

Quote:

Originally Posted by dan628

I found thins link on vivid racing, perhaps these would help?
Energy Suspension EVO8 Rear Differential Mount Bushing Set
http://ww2.vividracing.com/catalog/p...9ff1b3cfecff86

that sounds very similar to what was on the STi. The Diff housing had braces that reached to each side of the car, kind of a "moustache bar" as mentioned there. The bushings replaced were on the ends. It might be different for the Evo, but it sounds very similar.

Jasil · Apr 20, 2006, 07:39 PM

It happens everytime I powershift might have try the bushing kit and go from there.

Wheelhaus · Apr 20, 2006, 07:47 PM

yes, looks exactly the same.

occultworks · Apr 20, 2006, 07:52 PM

Everyone is talking about this happening with fast high rpm shifts. I get a clunk when I do quick low rpm shifts, like when I'm normally driving and not trying to pound on it. Is this normal and the same thing everyone else is talking about? It also doesn't happen when I engane and disengage the clutch slower, so I'm assuming it's the same thing.

Warrtalon · Apr 20, 2006, 08:32 PM

It can happen with a low rpm shift, too, but who does fast shifts at low rpm?

jesterEVO · Apr 20, 2006, 09:00 PM

lol i was just driving 5 mins ago and got the same loud boom when shift fast or whatever from 1-2. Glad this was brought up..i was worrying

texrex2002 · Apr 20, 2006, 10:28 PM

Quote:

Originally Posted by dayf

Didn't you have a WRX? Mine did the exact same thing on a quick 1-2 shift. Try not to side step the clutch is all I can say.

yes, still do actually, trying to sell it. Will try ebay on Sunday.

The wrx only made noise when I flat foot shifted 1-2 and sometimes 2-3 with launch control.

The evo seems to make all kinds of snicking noises with the synchros when shifted normally, and booming noises when shifted hard. I need to feather the clutch more.

oh, also it seems litk I HAVE to push the clutch all the way in on th evo th shift cleanly, whereas on my STi tranny I only needed to depress the clutch a little and i could get a clean, fast shift. must have something to do with the cables or something...

Warrtalon · Apr 20, 2006, 10:38 PM

That's just a function of where your clutch is adjusted. For instance, my clutch rod is way out, which makes the pedal engagement very high. I barely move the clutch pedal and it's fully disengaged. If the clutch pedal engages in the middle or low, then you have to do the full clutch depression.

Wheelhaus · Apr 20, 2006, 11:27 PM

I noticed an improvement in shift quality almost immediately after installing a stiffer front engine mount. The notchiness and grindy feeling are practically gone, as is most of the weird and seemingly inconsistent clutch feeling..

adx · Apr 21, 2006, 02:11 AM

I installed an ETD and havent experienced any clunks during shifting.