Clunking noise
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Guys,
Put the 408 into gear in the driveway on my way to work this morning and got a LOUD clunking noise. At first, I thought it was the flexplate to torque converter connection....but that was fine. It was a LOUD clunking noise....killed the truck a couple of times. I limped back to my driveway and took the Trailblazer to work instead. Anyone have any ideas what this could be? The flexplate bolts are fine... nothing else looks wrong...![Icon Confused](https://ls1tech.com/forums/images/smilies2/icon_confused.gif)
Stroker2112
Put the 408 into gear in the driveway on my way to work this morning and got a LOUD clunking noise. At first, I thought it was the flexplate to torque converter connection....but that was fine. It was a LOUD clunking noise....killed the truck a couple of times. I limped back to my driveway and took the Trailblazer to work instead. Anyone have any ideas what this could be? The flexplate bolts are fine... nothing else looks wrong...
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Stroker2112
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Guitsboy,
It was only when shifting from park into Reverse or Drive.....very little rpm....not continuos but LOUD! ...sounded really bad!.....I thought my flexplate had disconnected from the stall convertor or something...but that connection is tight. There are no leaks...metal shavings..etc anywhere to be found...my fear is that its in the tranny (its a new FLT level 5 4L60E)....
I guess I'll make the time to drop the tranny and examine closer......not sure what to look for though.....any other ideas before I starting tearing things apart?....
It was only when shifting from park into Reverse or Drive.....very little rpm....not continuos but LOUD! ...sounded really bad!.....I thought my flexplate had disconnected from the stall convertor or something...but that connection is tight. There are no leaks...metal shavings..etc anywhere to be found...my fear is that its in the tranny (its a new FLT level 5 4L60E)....
I guess I'll make the time to drop the tranny and examine closer......not sure what to look for though.....any other ideas before I starting tearing things apart?....
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Guitsboy,
It actually did sound slightly cyclical...like a "clunk-a-clunk-a-clunka"...
Would the gears in the transmission make that noise if it had bad line pressure (I've got a mech Vacuum mod installed to the master brake cyclindere)?
It actually did sound slightly cyclical...like a "clunk-a-clunk-a-clunka"...
Would the gears in the transmission make that noise if it had bad line pressure (I've got a mech Vacuum mod installed to the master brake cyclindere)?