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

[GTO 1]

Why do we, (Autos) have a 4 speed automatic, meaning 4 forward gears, but only have 3 gear selections L, I and D shift selections on the floor shifter?? Hmmmmm....

GTO 1

[DJVC]

i've been wondering about this too, its strange. when i have it in L it goes it has 1st and 2nd gear and then i shift to I without lifting off the gas i goes 2nd to 3rd, then the shift to D goes from 3rd to 4rd and then settles down.

[denmad]

I believe L is for low gears(ever get stuck in the mud? running through all your gears just makes it worse).
The I is for Incline I think and runs higher RPM.
The D is Drive(overdrive) and saves you gas by shifting more efficiently.

[Snake890217]

L & I?? I have 1 & 2 then D i guess they changed it since the 05s...

[Red07SSNA]

Our Cobalt's autotrannies are not like older trannies (05 has 1 2 D while 06-up have L I D). "L" holds the tranny in first until redline then shifts into second. "I" is for "spirited" driving and holds the tranny until 4K RPM from 2nd to third shift; it also downshifts as well as upshifting 3-2-1 and, of course, 1-2-3. It won't go into overdrive (4th). Using I makes the engine throttle input changes faster. "D" is the economy position allowing the tranny to upshift quickly into OD for fuel mileage -- but you get no engine braking when you let off the gas. 08's with the instant mileage in the DIC show 99 MPG when you are going downhill with the throttle closed (engine shuts off the fuel, I'm told, in that condition to get the most mileage).

[xyankees214x]

I is for intermediate. It should be used when towing something, it provides less shifting back and forth between gears, and low is obvious for the low end power and torque. I dont understand why people shift in there auto cars. You spent the extra money for the luxary of not having to shift and you do it anyway. And not to mention the long term negative effects this puts on a car. You really should not shift in an automatic car if you want it to last.

[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Your description of "I" -- Intermediate -- is outdated.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.

[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.

[Red07SSNA]

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.

Shifting is bad -- whew, I'm glad you guys mentioned it. Having never damaged an auto tranny in 30 years I better stop doing it cause maybe it will damage it. It's an "Old-Wives Tale" -- you guys are just perpetuating it! "L" is for increasing the internal strength of the tranny by increasing the line pressure. The Cobalt's tranny doesn't shift when you move the lever --it still shifts at pre-determined times -- regardless of lever position!!!!

Red07SSNA added 4 Minutes and 5 Seconds later...

Why do you suppose all the cars with "sport shifters" have them (the ratchet type shifters that you use to bump the tranny up or down one gear at a time). Do you suppose it is the manufacturers way of getting you to manually shift your auto so you destroy it and have to buy another car? Common guys lets get real now......

[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....