my 99 C5 whines from engine bay when i pull on 1st, 2nd and 3rd,,
also,, sometimes when i race and shift from 1st to 2nd it feels like the torque is not delivered to tires as if i was going up hill or the traction control is on but it was actually off,,

are these issues related or i am having many troubles?

 

I would doubt it's a transmission issue. Sounds like clutch issue.

 

i thought of the clutch,, does the clutch whine if gone?
if it slipped,, the rpm would go high?

 

I was thinking the same thing..possible clutch starting to slip.

 

Without listening to the noise I couldn't tell you but you did state the noise is near the engine. You should smell clutch burning also.

 

You may want to try and change the clutch fluid before turning any bolts. Don't know how many miles are on the clock, but dirty clutch fluid reaks havoc on the clutch. There is a few post discribing how to change the fluid with a syringe on the forum. Less than 30 minute job.

 

does it happen at partial throttle or WOT? could just be the sound of the AIR pump.

 

a new mcleod dual clutch is going in anyway with all bearings and required hydraulics,, and a remote bleeder

 

on both cases,, the noise is most noticeable after 3k rpm,, it sounds just like twin screw supercharger,, kinda like it
i have long tubes and AIR and EGR disconnected,,

 

also,, i hear the drive train whines when cruising @ steady speeds and low rpm (maybe coz it is quieter),, the whining goes when i left off the gas,,

any ideas?

 

Mine did this "whine" sound which really did sound kind of cool too me as well. I never figured out what it was and it slowly quit doing it. I assumed it was a bearing letting go somewhere but never could find one. Oil looked good with no metal in it and so on. However, I did end up replacing the transmission when it failed the last time, so I tend to think that is where it was coming from. Mine was a '99 as well. Now the question I have for you, what month was it put together? Its on the door label... if it was an early '99 then a real possibility exists that you ended up with a BorgWarner transmission rather than the more desired Tremec. The identification is on top of the transmission with a metal formed "BW" in the metal top. If its a Tremec, it'll clearly say Tremec. Now, if its a BW, have you changed the tranny fluid and if so, what did you use? Again, if its a BW, Do Not Use Mobil1 trans fluid in there. Good stuff but not for the BW transmission and you'll have a very costly repair...I know all too well.

Let me add here now too, my differential never showed any leakage but when I went to change its fluid, I found it had less than 1/2 quart in it instead of the 1.6 quarts it should have had. 75W90 w/friction modifer from GM

 

Its unlikely you heard that transmission from under the hood, being that it's in located in the rear of the car. The only thing that whines under the hood is the power steering pump.