hottrodd57

every once in a while, when I let the clutch out and in 1st or reverse in the first second i can heard a sound in the back half of the car which sounds like a marble rolling around in a large tin can, also once in awhile i can hear it when I slow down (10-30mph) and me turning????????? i took it to the dealer they said it is the trans or the rearend, or possible the clutch? but they would not know until they start tearing it apart!!! I had them check the trans fuild and rearend fuild both are full!!!!! does anyone know or had this problem ??? :confused:


[Modified by hottrodd57, 5:19 PM 4/30/2002]

Snowman

What year and how many miles on your car?

jerryv

The 'marbles in a can' noise is fairly famous. Do a search for 'marble' and you'll probably find lots of references. It is also mentioned in the video, and is apparently caused by the geometry of the drivetrain, including the rear-mounted trans. It is considered 'normal' and isn't indicative of a problem.

DJTJ

watch the video... "This is not a problem with the c5, just an inherant trait" or something like that....

ersatz928

GM considers it "normal". It is caused by the use of low viscosity ATF (automatic transmission fluid) in the manual gearbox, which does not damp the vibrations of the gears ratteling on the mainshaft. The thinner ATF (rather than gearbox oil) is used to gain some fuel economy, probably 0.2MPG! I'd sacrifice that for a car that doesn't sound like a piece-of-junk when I idle in nuetral or take off!!!!!!!!

zcobra1

My C5 makes more noise than others I have driven/heard. What is the best fluid for my MN6 manual to "minimize" the marbles noise ?? Can you use a heavier viscosity to deaden some of this noise ?
The noise is so bad and bothers me so much that I will give up some shifting smoothness if need be. The car is a 2002 so I do not want to kill the warranty-open to any suggestions from those that have made the awful noise go away.

mbtc5vette

I recently replaced my MN6 trans fluid with Mobil1 ATF and diff fluid with Mobil1 75w-90 gear lube + GM additive. I haven't noticed the "marbles" effect as much since.

leadfoot4

Just my $.02 worth......I think that there is also a little noise thrown into the mix by the serpentine belt tensioner. I've seen them move to and fro as the engine changes RPM or load. The change of load would occur when letting out the clutch and getting the car in motion. Mine makes the noise, and this is when it is most prevalent, so I personally think that this is part of the deal.

TVSKIP

THIS IS A GOOD QUESTION..........CAN WE SWITCH TO A MANUAL TRANS. OIL WITHOUT SUFFERING ANY TRANNY DAMAGE, OR ARE WE STUCK WITH ATF?

mbtc5vette

I sure wouldn't switch from ATF to gear oil in the trans. Others may have more technical reasons pro/con but if you have a warranty repair issue with your trans, you wouldn't have a prayer if they found gear oil in there. :cheers:

Crushinator

Your car is a brand new 2002 with a full warranty and makes a noise that it shouldn't. New cars don't make noises like that, regardless of what any video says. I don't understand a car company like GM that says these noises are normal, especially on a $50,000 Corvette! This isn't a freaken Kia we're talking about here. If I were you, I'd demand that the car be fixed 100%. That's just plain BS in my opinion that they say it's normal! :mad

02-C5

My 2002 make the same noise, esp. up hill with a gradual clutch release. Then again my 99 Z28 made the same, yet quieter, noise. I'm use to it.

NICKNICK

Just a rumor, but from a fairly reliable source, the C7 due out in 2015 will have a marble muffler that will eliminate the cheap, crappy sound. Sorry C6 fans. Nick :)

jcbuncc

NO switching your oil. Auto trans oil has a bit of grit in it to help the automatic discs lock up. This oil is..for lack of a better term...gritty. If you put a std type oil you will lose the auto trans all together in a short time.