Another "WTF is this noise" thread...

**BashamWS6** · 11-27-2010, 03:50 PM

This is what it sounds like...
The noise sounds like a clicking rattle (like when the batterys dead and the car wont start.)

This is when it happens...
1st-5th gear after 3000rpm
then as it warms up it will start clicking after 1900rpm

it doesnt affect my performance or shifting...
in fact at WOT in 3rd n 4th it stops...
But it always does it with partial throttle...

Location
i think its around the throttle body...

When i have the clutch held in it wont do it...
when im parked and rev it wont do it...
when i let off the clutch after switchin gears itll start clickin when it catches then stop until i hit the higher rpm...

Oh...and when i let off the gas...it quits as well...

Help!!!!

**Cutlass** · 11-27-2010, 05:38 PM

Does it change with engine rpm or vehicle speed?

**0rion** · 11-27-2010, 08:29 PM

almost impossible to diagnose these types of noises on the board......the best we can do is guess and give you things to look at it. I would say first it's very important to figure out exactly what area it's coming from. Not much up near the tb except belts and pulleys. Could be an exhaust leak, could be a cracked flywheel, could be a valvetrain issue, and several other things. Narrow down the location and start eliminating things in order of ease and cost. Do you have air pipes and egr on the headers? If so check those pipes for a blown gasket.

**BashamWS6** · 11-27-2010, 09:51 PM

I think its rpm...cuz i had my rpm over 3000 in 6th (about 125mph)... And it didnt click/rattle...
I have my stock exhaust still on but it will be replaced this week so thatll see if its any exhaust componets...
Umm a little confession....
Ran into a corvette on the road and was playing with him...i went to pass em and dropped it to third running 75 already i stayed in 3rd until it started to cutout and dropped it into 4th hard... I didnt notice the click/rattle until about 20 miles later...
And tonight i noticed that fourth grinds alll the time
now.... So i could narrow it down from there...
Fml...

**0rion** · 11-27-2010, 10:10 PM

that over rev would've been nice info to have. The clicking is most likely a bent pushrod. Not sure about the grinding issue as I'm an auto guy.

**BashamWS6** · 11-27-2010, 11:36 PM

Bent pushrod...perfect
well is there anyway to check that?
And wouldnt it rattle/click while reving as well if that wa the case?

**Spikito** · 11-28-2010, 05:54 AM

sounds to me like it could be the shroud around the clutch? theres a little piece of heat shield that clicked on my camaro

**35th-ANV-SS** · 11-28-2010, 06:13 AM

Originally Posted by BashamWS6

Bent pushrod...perfect
well is there anyway to check that?
And wouldnt it rattle/click while reving as well if that wa the case?

If you have a bent pushrod, it would probably sound more like a banging noise all the time. A bad lifter would be more like a ticking noise and as you rev it would get noticeably louder.

The only way to tell if the pushrod is bent, is to remove them and roll them on a flat surface (such as a piece of glass). If any of them are bent, I would just replace them all. It's an easy job to do and not that expensive.

Ticking could also be a lifter. Is your oil pressure normal?

Lastly, not to scare you, but it could also be a rod bearing...which would not be good for you.

**35th-ANV-SS** · 11-28-2010, 06:15 AM

Forgot to mention your grinding issue.

Are you saying 4th gear grinds when you try to shift into 4th? If so, you have either a) a broken synchro in your transmission or b) a bent 3-4 shift fork in your transmission.

Grinding is almost always indicative of a bad synchro. Does the shifter ever pop out of gear?

**BashamWS6** · 11-28-2010, 10:16 AM

Originally Posted by 35th-ANV-SS

If you have a bent pushrod, it would probably sound more like a banging noise all the time. A bad lifter would be more like a ticking noise and as you rev it would get noticeably louder.

The only way to tell if the pushrod is bent, is to remove them and roll them on a flat surface (such as a piece of glass). If any of them are bent, I would just replace them all. It's an easy job to do and not that expensive.

Ticking could also be a lifter. Is your oil pressure normal?

Lastly, not to scare you, but it could also be a rod bearing...which would not be good for you.

well its a ticking sound not a banging...
a bad lifter..if thats the case... again wouldnt it do it with reving in neutral too? this noise only happens when im actually driving...??

and rod bearing meaning...? (sorry im not very educated with internal components..)

Originally Posted by 35th-ANV-SS

Forgot to mention your grinding issue.

Are you saying 4th gear grinds when you try to shift into 4th? If so, you have either a) a broken synchro in your transmission or b) a bent 3-4 shift fork in your transmission.

Grinding is almost always indicative of a bad synchro. Does the shifter ever pop out of gear?

ill probably have the shop check the entire car from nose to tail being it hasnt been since i bought it...
the shift very rarely pops out of fourth if i pop th clutch too quickly...but it does happen.
whats the ballpark figure on building up shift forks and fixing the synchro?
i am due for a clutch and a MC...and ive been told to get a speedbleeder as well....so this would probably be the ideal time to work on this as well

**35th-ANV-SS** · 11-29-2010, 11:59 AM

Originally Posted by BashamWS6

whats the ballpark figure on building up shift forks and fixing the synchro?
i am due for a clutch and a MC...and ive been told to get a speedbleeder as well....so this would probably be the ideal time to work on this as well

If you are changing the clutch the transmission will need to be pulled anyway so you are right, any internal upgrades would be ideal to change out now.

The parts are pretty inexpensive, it's the labor that kills. I paid around 2K to have my T56 built by RPM Transmission, which included removing it and re-installing it. I got more than just the shift fork and synchros upgraded though.

If you are hearing a ticking at lower RPM and then not at higher RPM it could definitely be a bad lifter. The more RPM, the more oil pressure you have which would quiet the noise down with the added lubrication.

I don't really have an answer if this only happens while driving....

Have you tried to pinpoint where the actual sound is coming from using a Stethoscope?

**Smittro** · 11-29-2010, 12:11 PM

I'd have a look @ your tensioner too/also and the idler pulley.. If the spring becomes weak they like to chatter/rattle sometimes.. The grinding from the tranny could be a number of things most of which I think have been addressed by others.. If it is the trany maybe time to bullet proof it.. imho Good luck man..

**SSwt00SS** · 11-29-2010, 06:33 PM

my money is on a rod bearing(s) or clutch/pilot bearing issues...more so on rod bearings...

**Smittro** · 11-29-2010, 08:45 PM

Originally Posted by SSwt00SS

my money is on a rod bearing(s) or clutch/pilot bearing issues...more so on rod bearings...

Borrowed time if so..imho

**Too Fast** · 11-30-2010, 02:46 AM

Also the noise could be a bad throw-out bearing, surpised nobody's mentioned that. The clue is you say the noise goes away when the clutch pedal is depressed. But usually a throw-out bearing makes more of a squeaking/whirring noise that changes w/RPM. This bearing will get replaced with a clutch job, so make sure the new clutch kit has it supplied.

**BashamWS6** · 11-30-2010, 08:08 AM

so... worst case scenario...what will happen if this goes unfixed?

and if i get my transmission rebuilt and clutch replaced...were looking at $3000 including MC and speedbleeder

and how much would a throwout bearing cost?
rod bearings or clutch/pilot bearing cost?
tensioner cost?
idler pulley cost?
would i replace these with GM parts or aftermarket?

**SSwt00SS** · 11-30-2010, 09:46 AM

Originally Posted by BashamWS6

so... worst case scenario...what will happen if this goes unfixed?

you will have a 3500 pound paper weight...

**Smittro** · 11-30-2010, 09:55 AM

Originally Posted by BashamWS6

so... worst case scenario...what will happen if this goes unfixed?

and if i get my transmission rebuilt and clutch replaced...were looking at $3000 including MC and speedbleeder

and how much would a throwout bearing cost?
rod bearings or clutch/pilot bearing cost?
tensioner cost?
idler pulley cost?
would i replace these with GM parts or aftermarket?

If a rod bearing is bad @ the minimum you're looking @ needing the crank repaired.. Most likely if it's being driven with a spun bearing the crank will be junk..

I'd check with GM Parts Dirrect (sponser) they may be able to help with pricing of the other things mentioned..

If you're driving on a bad rod bearing what is happening is metal is being distributed throughout the entire engine oil system.. The more you run it the more wide spread the damage becomes.. Then BOOM or engine seize..

**BashamWS6** · 11-30-2010, 09:57 AM

great. ill get itin the shop next week and have them check out to see if its a throwout bearing, rod bearings ,clutch/pilot bearing, tensioner, idler pulley, tranny, lifters, or a pushrods....for starters