noise when slowing down in gear

[_Madman_]

Same problem here. My tranny was rebuilt and rewelded after the differential exploded. Now I have Fidanza lightweight flywheel, Fidanza 3.2 clutch and differential from Galant V6. The noise is pretty unpleasant. Especially when you release the throttle at 3-4k RPMs in 3rd gear, but happens in all of them. Sound is there even if you just rev in neutral with clutch engaged, as soon as you disengage, sound disappears. Also the 1st gear whines. I drive GST and sound is coming from tranny.

Oh, forgot to mention, tranny exploded again today. I easily stepped on the gas, one tire went loose and something broke. Now it has a sound that accelerates if you go faster and at 15 mph it's around 2 knocks per second.

 

[gstryyder]

i have the same noise with my car GST going on... been like that for a while. can't figure out what the hell it is.

 

[daren_p]

Guess I'll add to this post as well. After awd swap, new TRE Stage 3 tranny, Jacks rebuilt transfercase & rear diff, DSS level 2 axles all around, new U joints in the DS. MT-90 in the tranny, HD Shockproof in transfer & diff. Act streetlight flywheel, Fidanza 4.1 (6 puck sprung) clutch.

No noise on acceleration, noise on deceleration with clutch out & letting off gas. Push the clutch in or put in neutral, noise goes away.

I have heard of 1g's having to properly shim the driveshaft & was going to try this with my 2g to see if I noticed any difference. Also going to verify backlash in transfercase & diff, & get driveshaft rebalanced. Wish I knew about this issue before, as I would have got the flywheel & clutch balanced before their install.

Also when the car was fwd, I ran the same ACT lightened flywheel with a CFDF clutch. I had zero noises, I would think this noise should only be an issue for awd vehicles, if your fwd is doing this, I'm thinking there's bigger issues....

Edit: More info: Also have UMS tuning urthane/metal diff bushings & am running 235/40/18 Rubber (Kumho XS), as someone mentioned stiffer tire sidewalls made a difference on his setup.

 

[lowexpectations]

Guess I'll add to this post as well. After awd swap, new TRE Stage 3 tranny, Jacks rebuilt transfercase & rear diff, DSS level 2 axles all around, new CV joints in the DS. MT-90 in the tranny, HD Shockproof in transfer & diff. Act streetlight flywheel, Fidanza 4.1 (6 puck sprung) clutch.

No noise on acceleration, noise on deceleration with clutch out & letting off gas. Push the clutch in or put in neutral, noise goes away.

I have heard of 1g's having to properly shim the driveshaft & was going to try this with my 2g to see if I noticed any difference. Also going to verify backlash in transfercase & diff, & get driveshaft rebalanced. Wish I knew about this issue before, as I would have got the flywheel & clutch balanced before their install.

Also when the car was fwd, I ran the same ACT lightened flywheel with a CFDF clutch. I had zero noises, I would think this noise should only be an issue for awd vehicles, if your fwd is doing this, I'm thinking there's bigger issues....

I have spoken with Lucas over at English Racing quite extensively about this and it is my understanding that the noise we are hearing is coming from the rear end and is reverberating through the driveline and it sounds like it is coming from the front of the car when it is actually coming from the rear end. We may shim my driveline/rear end in the near future but so far I have not found any issues with driving mine this way. It is rather annoying and does go away as soon as clutch pedal is depressed and as soon as you begin to accelerate. In my car I mainly notice it around the 3k rpm range and the sound does seem to change pitch a little with rpm. I do have solid motor mounts in my car which I think helps to amplify this sound. I did not balance my flywheel and quartermaster twin during install.

 

[Gooberlog]

I too have the howling noise on decell at mid rpms. I have a ACT 2100 and lightened stock flywheel but i just topped off my trans so there is fluid. My old car did this too. Syncros are on there way out as well, so it may or may not go away once it's rebuilt.

 

[Drifte]

I'd like to know what is involved with shimming and what not. Im a bit confused their. Also wondering if any thing can be done with the rear end, can it be rebuilt, I hear theirs bearings, can I replace them?

I have new: transmission, driveshaft (entirely. And have replaced the fluids in the transfer case and rear end with redline HD shock proof. The noise was their before any maintenance was done, and after. This includes changing from a stock clutch/flywheel to the now spec stage 3 with fidanza aluminum. The only thing I can think of is the rear end had little fluid and very metallic fluid when I drained it.

I have to imagine this noise is audible from outside the car, as its so loud and sounds like it cant be good. I need to get the car on a hoist and really look it over, see what may be happening.

 

[eclipsh]

Just thought I'd throw my .02 worth of experience into this. I've had this noise be caused by three different things.

First was flywheel bolts that were backing out. The Chilton's I first got with my 1g listed the wrong torque specs and the bolts backed out on me repeatedly until I checked another source for the torque specs. That made one hell of a noise. Incidentally, the factory manual says 109 ft lbs is the right number.

The next noise came from the clutch springs banging back and forth. The flywheel bolt heads had worn the springs a bit and they were loose enough to rattle when RPMs changed. This was easy to hear through the bell housing with a mechanic's stethoscope by revving the engine in neutral. I couldn't tell what the cause was until I had it out though.

The third time it was gear noise from the transfer case leaking fluid through the rear seal. It started to seize on me at 50mph and finally locked at 20mph. Factory recall took care of that.

The flywheel bots were very loud and could be heard all the time. The other two were noticeable whenever I was coasting/engine breaking. The clutch springs sounded a LOT like gears grinding but of course it wasn't.