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I posted this on I-club and did some other research to get a few answers, some typical I-club flames-some helpful. Basically baby shift and/or urethane mounts. The rearend has a clunk between 1st and 2nd during hard acceleration. In my opinion it clunks pretty easily. ??No one replied to the delay in engagement between the front and rear. It seems like the front matches the clutch engagement but the rear has a split second delay, then the clunk. Any opinions on the delay?



>Somewhere in the rearend clunks between 1st & 2nd during hard acceleration. It's like their is a split second difference between the front and rear receiving the torque. The front wheels seem to match the clutch engaging but the rear seems to lack and clucks or jolts as it receives the power.

Or I wonder If I'm driving it too hard. I'm use to have a lot of big & smallblock Camero's, Elcamino's, Nova's so I'm use to dropping the clutch and smashing the gas between gears. One car was pretty quick and I had to baby the loud pedal between gears, more engaging the clutch and less gas at engagement and ease on the gas or it's would spin the tires too much. Do you have do this method, not from to much power but due to AWD or weaker mounted rearend or design?<



>Thanks I'll stop banging the gears between 1st and 2nd. Didn't think I was doing it that hard(compared to past hotrods), but it looks like I'm still am. I'll make sure I baby it next time. I may look into the urathene mounts too, sure seems to clunk pretty easily.

Anything about the delay in time between the front to rear engaging?<
 

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I hear the clunk everytime I shift in a "spirited" manner. I used to cringe at the sound, but figure it's a housing to floorpan noise (or mount to mounting surface noise) and not an "internal/mechanism" noise so I'll learn to live with it. :)

I never noticed the delayed engagement - but it would make sense. There are numerous joints/mechnaisms that would delay the transfer of force from the front of the vehicle to the rear... I wonder if there's any damage being done?

Aloha,
Richard...
 

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This is typical. When I got my rex, I was used ot Hondas which have awesome, near bullet proof trannies. When I shifted fast it would clunk hard, so I slowed my shifts down so it didn't do that. I'm sure I could run a tad faster banging gears, but I'm trying to make the tranny last. The tranny/drivetrain clunks/thuds because all the tq is absorbed instead of spinning/chirping like in a 2wd car. I'd be careful.

-C
 

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TypeC,

If I could pull off 13.0's @ 105mph without shifting with a clunk I'd do it that way too! :)

Aloha,
Richard...
 

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i hear a clunk too

i put my 4Dr DRW on the track tonight ran a 13.8. that was my best with up, down pipes. i have notice a clunk in hard shifting. not grinding gears but poping the clutch. should i have anythign to worry aobut and should i baby it more, no hard launches. any info would be cool
 

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Have any of you guys tried adjusting your shifting technique? The reason I ask is that I only hear a clunk from the rear end when shifting VERY easy - really only when leaving the house in the morning which means going easy to warm up and going downhill. Sometimes when cruising slowly looking for a parking space too. I'm pretty sure that it's because I'm completely unloading the drivetrain in these cases, so it has to take up slack, hence the clunk. I never get it when going up through the gears quickly. That's why I suspect it might have to do with your particular timing during shifting.

C
 

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for dsms the thud usually comes from the carrier bearing receiving the tq from the drive shaft. could it be same for you guys as well?
 

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GV27 said:
Have any of you guys tried adjusting your shifting technique? The reason I ask is that I only hear a clunk from the rear end when shifting VERY easy - really only when leaving the house in the morning which means going easy to warm up and going downhill. Sometimes when cruising slowly looking for a parking space too. I'm pretty sure that it's because I'm completely unloading the drivetrain in these cases, so it has to take up slack, hence the clunk. I never get it when going up through the gears quickly. That's why I suspect it might have to do with your particular timing during shifting.

C
No, it's quite the oposite. If you shift as fast as possible without powershifting, it'll clunk for sure. Everytime. I was used to my GSR where I could slam it into gear (not using hard force, but put it in very quickly and SLAM the clutch in and out). The sound isn't really a *clunk*, but more of a *thud*
 

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there are some bushing and brace kits to prevent te clunk, someone posted the link awhile ago. i wonder if it adds much stress to the rear diff. since the bushings would no longer absorb as much of the shock?
 

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TypeC said:


No, it's quite the oposite. If you shift as fast as possible without powershifting, it'll clunk for sure. Everytime. I was used to my GSR where I could slam it into gear (not using hard force, but put it in very quickly and SLAM the clutch in and out). The sound isn't really a *clunk*, but more of a *thud*
Yeah, but that's what I'm saying about sdjusting your timing a bit. We both get the same symptom, but in different situations. Mine never cluncks when shifting fast.
 

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dukmahsik said:
for dsms the thud usually comes from the carrier bearing receiving the tq from the drive shaft. could it be same for you guys as well?
Interesting. I'm getting a low rumble noise from 40-80 no matte what gear I'm in under acceleration. Could the carrier bearing be causing this? It's only under load, and does it more-so when in cold (-40 degrees) weather.:confused:
 

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How many of you guys have aftermarket exhausts? My buddy's got an 03 with the HKS Hiper and he noticed that on firm 1-2 shifts he would get a clunking noise after the exhaust was installed. He figured it was hitting something so he put polyurethane hangers on and the problem went away. I've got the Greddy EVO and have similar problems, but it's more that the exhaust wants to shift out of the rearmost driver's side hanger...


-Andy
 

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i have whiteline rear differential bushings, cost 20 bucks, removes the thump. It even says it does on the instructions. It replaces the uber super soft rear bushings with harder polyurethane bushings. Good if u ever goto the track or cant help from shifting fast - again 20 bucks cant hurt anything. I got mine from www.subaruwrxparts.com
 

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GV27 said:
Have any of you guys tried adjusting your shifting technique? The reason I ask is that I only hear a clunk from the rear end when shifting VERY easy - really only when leaving the house in the morning which means going easy to warm up and going downhill.
I get this same "clunk" when I'm driving slow going from 1st to 2nd. I noticed that if I shift at a little higher RPM it goes away. :confused:
 
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