Nasty rattling on deceleration

[IronMonkeyL255]

So, my clutch finally gave up the ghost. Just shy of 100k miles on an OEM '06 WRX clutch that came with my '06 tranny and rear diff. I replaced it with a Clutchmasters clutch and lightweight flywheel about a week ago. While I had everything torn down, I noticed the boot was torn on one of my front CVs, so I replaced the axle. Now, when I am decelerating in gear, it makes an obnoxious rattle between 40 and 60 mph. It seems to be coming from the right front (I hear it to my right, and someone riding in the passenger seat said he heard it from in front of him). I thought axle, because I didn't recognize the brand that he picked up (he went to the parts store to grab it while I was still tearing stuff down), so I swapped it out for another one (both were new axles) of a brand I have used before with no issues. It is still there.

It seems to be speed dependent (doesn't happen at higher or lower speeds), and independent of gear (does it in 3rd, 4th and 5th indiscriminately). It only does it when I am off the gas and in gear (as soon as I push in the clutch or press the gas, it goes away). Everything else about it seems fine. Clutch feels great (albeit a little grabby, being a stage 2 clutch), although it seems the throwout bearing may have been a little cheap, because if I slowly push in the clutch it makes a different kind of rattle, but if I push it in quickly it is silent.

Next thing I am gonna try is switching the axles from side to side and see if it follows. It seems unusual, but I could have gotten 2 bad axles (I would not be at all surprised if they were remanufactured, but new...?). I lubed the piss out of all the contact points of everything putting it back together, and used loctite on the flywheel bolts and the pressure plate bolts just like I always do. Everything went together as smoothly as usual, so I don't have much clue what it could be.

If it's not the axle, I am at a loss. I can't really think of what else it could be. I checked everything else I could think of and it all looks normal (wheel bearings, brakes, ball joints, nothing even close that could be rubbing, etc). I hope it's not anything involving tranny internals, but I can't think of a way to check without tearing the thing apart (which is impossible at the moment since I no longer have a backup car).

[IronMonkeyL255]

Well, not the axles. Swapped them from side to side and got no change. Gonna have to pull everything apart, it looks like.

[Legacy777]

This might be a long shot, but check out this thread.

http://forums.nasioc.com/forums/showthr ... ?t=2092146

[IronMonkeyL255]

Good find. Sounds like exactly what it is. Guess I'll just ignore it then. Well, maybe I'll pull everything apart to replace the shitty throwout bearing, but if that is all it is I can live with it.

[BoostedSubie]

I have an Excedy stage II clutch in my Impreza and I get a similar noise under decel as well. Like you, I keep checking everything under the car, and can't find anything that would be making noise. I had never heard of the spring thing with the clutch till Josh posted that.

[IronMonkeyL255]

Mine is pretty prevalent. I may switch out the gear oil (I am currently running Redline lightweight shockproof, which they say makes it worse) and change up my tire pressures a bit to try to calm it down a little, but as long as I know what it is I can live with it until it wears out.

[Legacy777]

I found that when I was looking at clutches for the 6spd and decided to stick with the OEM clutch as a result.