2008 Chevrolet Cobalt transmission issues

smittydog

My rpm's flutter about 500 -700 while driving 1500-2000 rpm's. Speed 30-45 and again 50-60. Feels like it down shifting. Researched and have narrowed down i hope. Torque converter clutch, valve body or solenoid issue. Let me know if im off base.
I sent email to GM customer service and my local chevy dealer/ service center.
My Name
My Address 
Ingleside tx. 78362
2008 cobalt ls
57,034 miles
Vin#1G1AK58F587265299
Bought this car 4 days ago 4/30/2015. Driving home saturday it started acting up. Pulled into local transmission shop paid 60 bucks and they told me torque converter problem and to take to dealer. Should still be under waranty. Had a buddy trailor me home as i didnt want any safety issues or catastrophic damage done. This blows. Hitching to working with a 4 day old $5,500 car sitting in driveway. I hpe they contact me soon. Thanks for letting me vent.

stever

The "regular" warranty is 5 years / 100,000 miles for the '08 Cobalt. GM has offered up a 10 year / 120k mile extension for some models but that's for wave plate issues. Don't be shocked if GM claims they are unrelated issues, assuming the other shop's diagnosis is right (and assuming that the Cobalt is covered by the warranty extension).

smittydog

Update... not. Damn car is still sitting. Trailored it to the local GM dealer i bought it from.Dealership drove it and did a ride along with me, the tech says its normal. Starting to shift hard. Now its 500 to 1000 rpm jump at these speeds 18-20 mph, 27-30 mph, 37-40 mph, 43-45 mph, 53-57 mph. All the shifting points. Two long stretches of road i drive 35 break kneck for 6 miles. Then another spot i drive 55 for 5 miles. Rpm's jump back and forth 2200 to 3000 constantly. Wish we had a lemon law. Take this [non-permissible content removed] back. Sucks i paid cash from dealership. Should have financed and let them repo.