LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

Grinding noises when downshifting

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Old May 20, 2003 | 03:58 PM
  #1  
kyzer soze's Avatar
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From: Los Angeles, CA
Grinding noises when downshifting

Sunday i was driving my car. When im in say 4th gear and im slowing down i'll shift into 3rdwhen i push the clutch down then move the shifter the shifter starts to make a bunch of grinding sounds. It shouldn't be doing this because my foot is still down on the clutch. What could cause this?

It did this once before (4 months ago) when i had my stock shifter.
Old May 20, 2003 | 04:25 PM
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From: Northern California
Sounds like a bad syncro.
Old May 20, 2003 | 04:37 PM
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kyzer soze's Avatar
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^^^^ how bad is that? Is that expensive to fix? What kind of place should i take it to get it checked out? Your in Los angeles?

thanks
Old May 20, 2003 | 05:20 PM
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From: Northern California
It's expensive to perform any tranmission work. Before having your snycros changed try a different tranny fluid. I might recommend Honda ATF or Redline ATF. If the noise doesn't stop with the fluid change you're looking at around $700 to $1000 for parts and labor. Any transmission shop can fix a T56 tranny.

You can live with a bad syncro without problems most of the time. You indicate that it only happens once in a while. Unless it's a problem you have all the time I wouldn't worry but do try a new tranny fluid.
Old May 21, 2003 | 12:24 AM
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Most likely cause is a syncro as stated above. There are other things that could cause the grinding, but becuase you said its only happened a few times its probably one of the syncros starting to wear. New Fluid might help.
Old May 21, 2003 | 12:31 AM
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kyzer soze's Avatar
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Thanks guys i couldn't find honda or redline so i got :

castrol dexron III mercon ATF

Is this fine?
Old May 21, 2003 | 01:01 AM
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That's fine. Any Dextron III will do.
Old May 22, 2003 | 03:15 AM
  #8  
kyzer soze's Avatar
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Alright thanks man! I ran into a problem though i don't have a dipstick for my transmission fluid. I have two seperate books for my car (haynes manual and the one that came with the car) and it shows a pic of where my dipstick should be but their isn't one. I guess i'll have to take it to the dealer.
Old May 22, 2003 | 11:43 PM
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From: Old Bridge, NJ 08857
I've never seen a manual transmission with a dipstick..at least not in f-bodies (as I haven't done any real work on other manual transmissions or manual transmission cars...)

But...you have a fill plug and a drain plug. The way you know how you have enough fluid in there is when the the fluid comes out of the fill plug. Or you could do like I did, pour it in through the shifter, 3.8 quarts worth.
Old May 22, 2003 | 11:47 PM
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I've got a similar problem with my tranny. Is there a upgrade from the stock syncros?
Old May 23, 2003 | 12:13 AM
  #11  
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From: northglenn CO.
I had what sounds like that on my 93. We thought that the input shaft bearing was going bad so I pulled the tranny and we took it down to 3 peices just to see the bearing on the input . everything looked good so we put it back together and put it in the car went ahead and did a new clutch at the same time hoping that would help. nope problem was still there. got to thinking about it and took the tranny back out checked the pilot bearing.
the pilot bearing was letting the input shaft move causing a grinding noise in the tranny on down shifts at first from 4th to 3rd gradually getting worse in all gears on downshift. put a new updated bearing (from just brass to a needle bearing type setup) took care of it. had no more problems.

later nate
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