Jump to content
LegacyGT.com

Groan/rattle noise on deceleration


Recommended Posts

05 LGT wagon 5MT

I was taking my car over to the garage for a different issue, and noticed an odd sound when decelerating/coasting.  Seems to appear in any gear (only tried in 4th, 3rd and 2nd).  When accelerating or steady throttle, no noise.  Only happens when completely off throttle with the transmission in gear - clutch engaged.  It's a combination of a lower pitched groan and rattle.  Hoping it's not a clutch thing, just replaced a few years ago, and maybe put on 20k kms since. 

Not sure it makes a difference but the other issue I was taking the car in was to have the flanges welded together on my nameless mid to y pipe as the clamp decided to disintegrate on Friday.  The bolt that tightens/pinches it decided to go on permanent vacation, and I was able to rig something together to get it back on.  Maybe that is the cause?  Might be the rattling sound......I will be able to check when I pick up the car later.

Open to suggestions.  

Edited by GearJamr
Link to comment
Share on other sites

17 minutes ago, seanyb505 said:

My 5sp has always been a little noisy. What flywheel do you have? Any poly or hard rubber bushings (that might amplify any noises)?

Mine is supper loud with my clutch/fly and mounts. Sound like a dogbox when in gear and off the gas. The shop let me know it would do it with all new stuff. Car runs great.

Link to comment
Share on other sites

Welcome to the 1940's truck transmission. Mine made that noise for over 10 years. I learned early on to put it in neutral and coast to the stop sign, etc.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

Link to comment
Share on other sites

I had a similar issue on the car I just bought. Rattling from transmission tunnel when decelerating in any gear until it got below 2k rpm. No noise on acceleration or when in neutral. Turned out to be a loose bolt on the trans crossmember. The long horizontal piece closest to the front of the car. (Needs to be at 103 ft-lbs I believe) Found it by banging it w a rubber mallet. Made a clank of metal on metal. 

Link to comment
Share on other sites

Well, since it was a new noise it made my hair stand on end.  Turns out my suspicion was correct, it was due to the exhaust clamp.  After having the flanges welded, the noise is gone.  Actually, the exhaust is MUCH quieter on deceleration overall now.  Clamp must never have been tight enough from the beginning.  But I tightened it to the point where parts of the clamp were beginning to deform, so, glad it's welded and permanent.

Thanks for the input!

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×
×
  • Create New...

Important Information

Terms of Use