Why do we, (Autos) have a 4 speed......

[Red07SSNA]

Originally Posted by nugz

So while driving it doesnt hurt the tranny to shift from drive to 3rd when coming to a stoplight? I do that all the time, I love the sound it makes....

I do too...that's why I will keep mine in "I" around town Speed Limit < 45 MPH. Obviously common sense needs to be used -- don't go putting any auto shifter into low at highway speeds!!!!

Nugz -- the ex-YC admin guy?

[GTO 1]

Originally Posted by Red07SSNA

Your description of "I" -- Intermediate -- is outdated. In the Cobalt "I" gives full automatic with 1st - 2nd - and 3rd gear but the shift point at part throttle is raised to 4K RPM -- and it also downshifts aggressively as you slow down. Additionally, If you don't pull it into low and turn off the traction control when you get wheel spin the ECU backs off the timing to reduce power and your acceleration suffers (2.4L cars and 2.2 w/traction control). With the lever in "L" the valve body increases line pressure to support maximum torque from the engine -- it also shifts the tranny into 2nd perfectly at the redline -- no mis-judging on the driver's part. Shifting an automatic tranny does not reduce it's life -- if it did this would affect the warranty and the manufacturers of autotrannys wouldn't provide a way to shift it. I've been driving auto equipped cars for 30+ years -- and I have driven them aggressively while manually shifting them -- never had an auto go out on me. I also owned a 70 Ford for 27 years and drove it nearly every day to work using a B+M ratchet type shifter -- the third owner is still driving it.

Now THAT'S the answer I was looking for!! Thanks "Red07SSNA". Any more info you have on it? I enjoyed reading an detailed account of a question that had me shaking my head. And the owner's manual offers little/no explanation.


GTO 1

[DJVC]

So the answer is: That manual shifting will generally not hurt automatic cars?

[Red07SSNA]

No, shifting an auto tranny will not harm the tranny. Having said that, the Cobalt's tranny is unlike any tranny from the past -- no matter where the shift lever is positioned the tranny will shift at predetermined RPMs -- but where you have it will affect the performance. Let me explain:

I had an 06 LS and installed all the GMPP performance parts. I came across an 06 SS 2.4L and we squared off twice. I knew the lady driving the SS was trying because we both got wheel spin off-the-line. My LS proceded to "wax" her SS and I thought it was the GMPP performance parts that were giving me the edge (her SS 2.4L was stock - no accessories). Then I got the bug and traded in my LS for my 07 SS 2.4L and had all the GMPP performance parts installed by the dealer before I bought the car. First time I got "on it" I was DISAPPOINTED! My LS would kick the crap out of my 07 SS UNTIL I found out about the traction control. If you leave the shifter in "D" or "I" and start out with wheel spin the traction control kicks in and kills your performance -- and I do mean KILLS the performance. I found that when you have the shifter in "L" and turn off the traction control the performance is there. So when you have that kind of driver next to you at a light that knows the 4 lane turns into a 2 lane and he/she wants to get around you make sure you drop it to low! After the tranny shifts into second gear remember to shift into "I" so it'll go into 3rd gear.

[xxcooljay23xxg5]

Awesome thread and im glad someone felt like shedding light on the subject. I got an auto and i shift it as well. More fun.

[gre23a]

i do some auto stick driving, i was kinda wondering if it did have any negative effects on the tranny cause i can here some weird whinning sound coming from under the shifter. another thing i have notice while driving in I or L, is that the whole engine and trans seem to move around a lot as you give it gas then let off. i also noticed that the flex pipe on my down-pipe that mounts to the exhaust manifold is out of shape, this may have been caused by the engine/trans moving around a lot. any input there? i will try to get a pic of the part up.

[Red07SSNA]

Did you see the Redline TV show where they installed an Injen Intake and the GMPP performance exhaust on an 06 LS with SAI -- and then did dyno runs to check the HP increase? During the dyno runs you could see the engine jerking around quite a bit -- almost scary looking! All engines do this because of the rubber mounts. If the engine was secured to the chassis to prevent movement your teeth would probably hurt everytime you drove because the vibration would be nearly unbearable. If your flex joint is distorted have the dealer take a look at it and see if they will replace it under warranty -- and have them look at your mounts in case you have a broken one.

[gre23a]

hmm well the downpipe i have is off an ss/sc, i replaced the stock one. i may just have to by a nice aftermarket one. i dont think they would cover my ss/sc downpipe under warranty, maybe the motor mounts but not the downpipe. the car only has 6500 miles on it i hope the motor mount isnt out.

[Chevy Cobalt 08]

Originally Posted by DJVC

So the answer is: That manual shifting will generally not hurt automatic cars?

Originally Posted by biniecki

Yea manually shifting an auto is not good for it even if your just doing it for racing purposes. I have found that manually shifting while drag racing actually resulted in slower times. I just got the B&M shift+ kit and installed that for quicker shifting which has resulted in .2 sec faster times at the track and that was b4 i installed the polly bushings. Interested in seeing if i get even better times with them installed.

thats because you can red line each gear in a manual. since a automatic tranny works completely different than the gears in a manual, it's just bad and causes damage cause its not made to do that. which is why slower times cause the cant react like a manual can after each shift.

[DJVC]

Originally Posted by Chevy Cobalt 08

thats because you can red line each gear in a manual. since a automatic tranny works completely different than the gears in a manual, it's just bad and causes damage cause its not made to do that. which is why slower times cause the cant react like a manual can after each shift.

So is it really possible to do any real damage auto shifting and using the B&M Racing Shift Plus?