I bought my Cobalt new, 07 LS, now when I shift from 1st to 2nd or from 3rd to 2nd at anything higher than 5500 sometimes my gear grinds and then sinks into place. It doesn't happen all the time, only maybe 60%. I am still under warranty, 16,100 miles, I have been doing some looking, do we have electronic safety's on our clutches kicking in? I don't want to have to double clutch the thing everytime I want to race some schmuck on the street. Any ideas as to the cause?

Also my stereo keeps switching between Aux and whatever I'm listening to even though nothings plugged in, anyone else?

 

i recently had the same problem, but figured out that the souls of my shoes were shorter than my previous shoes, so im still getting used to pushing the clutch in a little more. Did you just get new shoes? lol not being a dick just saying

 

my friends vw does the same thing, only when he is at high rpms. but last night he was hitting the gas and mest it up more and it does it every time now... i would get it checked asap before it goes out.

 

synchro's

 

The grinding sound you're hearing is the synchros. Our 2.2s have a very heavy flywheel so when you let off the gas for the shift to 2nd (especially if you're revving high) it takes longer for the rpms to drop into the appropriate range than it does for you to shift. Because you are trying to engage a gear before the engine and wheel speeds match for that gear, you are hearing the synchros grind.

My suggestion, slow down your shifts to 2nd and don't try to force the shifter, instead let it slip into place. You may lose half a second in the 1/4, but you'll save your tranny.

Also, WTF are doing racing in a LS? First, street racing is dumb, second...IT'S AN LS!