I have an 07 Cobalt LS automatic with 708 miles (yes you read that right). Today I drove about 100 miles round trip. After driving around 75 miles, my car started jerking when the transmission would downshift from 2nd to 1st. It would also jerk upshifting from 1st to 2nd. I called the dealership as soon as I got home. The mechanic drove it back to the dealership, supposedly without the problem occuring. They thought it could be a computer problem that just needed to be upgraded or something of the such. They checked the fluid, etc and didn't find a problem. They are keeping the car over the weekend and attaching a scanner to it on Monday. They will drive it further and hope it reoccurs, so the scanner can catch it. Has anybody had this happen to them? The car isn't raced and has no mods.

Stephanie

 

I dunno, they will replace. They will have to.

 

I see you're in PA - what dealership? The service you will get will vary greatly. If you're in Western PA I can give you some tips and suggestions on who to talk to and who to avoid.

 

I am in Eastern PA. The dealership is Bob Weaver Chevy Superstore in Pottsville, PA. I just don't understand how the car was acting up right before they got here, and then it doesn't act up for them.

Stephanie

 

Thats the way it always works. Good luck!

 

I bet you didnt have it in D, you probably had it in L or I...

that would make it jerk a little when it downshifts, mechanic put it in D and didnt feel anything of course.

 

Actually it was in drive. I drove 75 miles before it started acting up. This wasnt a little jerk, as the car was jumping 3 feet after i stopped. Hopefully they find something.

 

It may not necessarily be a trans issue. I've got a similar situation with my 2007, 2.2L, 4T45E. I've read of two other 2007 owners with the same problem as me. Neither has been able to find a solution: https://www.cobaltss.net/forums/problems-service-maintenance-69/rpm-flutter-bounce-2007-2-2l-4t45e-81369/

 

Stick shift FTW

 

Thanks for your helpful contribution.

 

Well I got my car back last night. They road tested it a combined 78 miles and couldnt replicate the problem. They checked updates, calibrations, and bulletins. My car is up to date on everything, and there are no bulletins for this problem. So gave me the option of leaving it there and testing it more, or bringing it home. So I brought it home, and if it acts up again I am to call them back. So far it hasn't acted up. I'm hoping it was a one time fluke.

 

Mine does it occasionally... but mine's been absolutely thrashed on and the transmission mounts appear to be no longer in existence. Good stuff!

 

harsh up/down shifts in a trans can be caused by numerous things, seeing as i work at a chrysler dealer, i tear down trannies quite often, seeing that it has low milage, im guessing improper assy. from new. Could be water in trans, broken snap ring in clutch packs, plantary came appart, allmost anything can cause it. i had a Pt cruiser that could engage the reverse clutches for just a second when it shifted into third. almost threw you thru the windshield.

 

Well my car is in the shop again! I came out of Walmart and my car drifted 20 feet from where I parked it. This is an automatic, not a manual. So I told them keep it and fix it this time.

Stephanie

 

that last one sounds like it might have something to do with the parking paw this little arm that meshes with some teeth trans to keep it from moving in park the 2nd to first down shift jerk could be a number of things (like the 2-4 band catching or something) they may need to remove the trans and tear it completely down hope they fix it trans issues always suck!

 

Yeah hopefully it gets fixed this time. If not they have one more shot and I'll lemon law it. I have my paperwork together. They are contacting GM because they have never had a problem like this, and they don't know what to do.

Stephanie

 

Well I got my car back again! They have found nothing wrong with it surprise surprise. They called GM Technical Assistance and they have no documented cases of the same problem. They refuse to let the dealership investigate the problem further since it did not drift while in their shop. They have issued a case number in case it happens again or another person has the same problem. So, I'm calling a lawyer now.

Stephanie