I love my sonic. I do. Now that I got that out of the way...
I totally see where this guy is coming from. I have never... NEVER owned a car that would grind when you shift in the upper RPM's quickly. Not my cavalier... my mustang... my cobalt ss... my 1500 work truck... all sticks, no grinding whatsoever. Out of the many vehicles I have driven, the only ones that grind when shifting like this are...
1. Cars that have a problem
2. My fiances Cruze Eco and my Sonic RS.....
The Eco has 62k on it and will grind if you shift fast 1st to 2nd... same with 3rd.. so it doesn't go away.
The problem is that a vehicle when purchased should function correctly. I should be able to run the car into the upper RPMs, and shift quickly, and proceed with my acceleration without the car grinding. I don't see how people can be cool with their vehicle doing this, as this is not how a manual transmission should function. You all spent good money on your car just as I did..... We know the problem is very.... VERY common. GM sure as hell is aware of it... Yet there are no fixes presented besides, "Swap the tranny, wait for the grind again."
I absolutely do not think this guy is out of line, or that his frustration is unjustified. You purchase a brand new car off the lot expecting to get a perfect running car with no defects. The fiesta, focus, dart, mazda 3, 13 v6 camaro, 13 v6 mustang, and the veloster I ALL DROVE before making my decision to buy a sonic RS, did NOT grind at all in any shift. All allowed for red line shifts, all allowed for quick shifts, no problems at all.
I, for one, am very angry that these cars have a very notorious shifting problem. It will for sure influence my next car purchase as out of the 3 new Chevrolets I have driven, 2 of them grind.
Anyways, as for a "fix" I found slowing the 1st- 2nd shift and the 2nd - 3rd shift a tad makes the grind lessened or non existent. Otherwise slightly riding the clutch in between the shift seems to make the grind go away...