I have an auto LT and and love the auto but it dosnt have as much kick can I swap it out for the 2.4 auto because its geared for performance.

 

They are the same....

 

Are all the electronic controls the same? Does the 2.4 computer control the tranny the same way as the 2.2's (exact same wiring)? Since the ratio is 3.91 Vs 3.63 what needs to be done to the 2.2 computer so the speedo is correct, shift points aren't screwed up, etc -- and how do I get computer adjustments done?

 

Ones the t40 and the other is the t45 the t40(ss) has lower ratio gears I read it some were.

 

Auto tranny codes are MX0 (2.2) and MXN (2.4). Gear ratios are same, final drive ratio is the difference.

 

You can't get computer adjustments until HPTuners decides to support us.

The Cavalier uses the 4T40e

The Cobalt uses the 4T45e



The naming system is as follows:
4 - T - 45 - E
4 - Four Speed
T - Transverse Mounted
45 - Torque Handling Capabilites
e - Electronically controlled

 

SO how do I change my final drive ratio for more acceleration.

 

[QUOTE=HackAbuse]You can't get computer adjustments until HPTuners decides to support us.

The 2.2 computer can be adjusted for wheel size changes, can it be adjusted for final drive as well?

 

You buy a turbo. Leave the tranny alone bro.

 

[QUOTE=Cobalter LS]It can be changed for speedo calibration, but as for line pressures/shift points, they arent available yet.

 

[QUOTE=HackAbuse]You are mistaken Hack. The 4T45e tranny is supported by HP Tuners. You can have it programed. Just not the PCM yet....

 

you get more mods

 

Actualy I thought they would have been the same too but guess what?! They're not!
I know I couldn't believe it either! Anyway the 2.2 tranny has a final drive ratio of 3.63
and the 2.4 has 3.91. Again I know holy crap! LOL! Anyway heres the part #'s for the 2 different tranny's!
2.2 trans part #24233933
2.4 trans part #24233931

Now I'm not gonna swear to it but I would think they'd be able to be swapped with no serious issues but I've yet to have 2 in front of me to compair so I'm not 100% on that.

 

[QUOTE=RedBaseBolt]agreed, the 2.2 has tranny tuning cababilities thru hp tuners

 

We're all learning these cars because there's not much info out there for us -- this cobaltss.net forum is the best help yet. The 3.91s can replace the 3.63s. Putting lower gears in any car makes it accelerate quicker -- better than any other mods can do. In fact, once you have better gears all the other mods work that much better! I just finished rebuilding a Honda autotransaxle for my daughter's car -- the damn thing has 4.13:1 gears in it, stock!

I know how to build engines and trannys but the computer controlled systems and how to play with 'em are still new to me. I've just ordered the manuals for the '06 Cobalt from Helm -- I hope they shed some light in this area.

 

I'm curious where you're getting your numbers on the different final drive ratios on the 2.2 and 2.4 cars? Here's a screenshot of the specs off of GM Canada's website, which I've always believed to be accurate. (as opposed to the USA Chevy site, which I know gives inaccurate info on the 2.0's ratios)

 

[QUOTE=celicacobalt]You're right but according to my sources, you have to access the TCM thru the PCM, which isnt unlocked yet...

 

My parts computer here at work. I'm sorry I have no way to link you to the page but it shows the 2.4 and 2.2 do in fact have different transmissions and those are the final drive ratios I listed. If you go to a GM dealer have them pull it up and you can look on the screen yourself thats the best I can tell you.

 

Interesting...the 2.4 must be a hell of an efficient engine, then. It has the same EPA rating as the 2.2, despite being larger, more powerful, and having the shorter gearing. Is VVT responsible for all that?

 

Does anyone know how to download something to link from a secure web page? I found a page in the GM service manual on line that shows the different ratios but I can't link to it.
When I try it just says I'm not permited to view the page when I try and open the link from here.

Any ideas?

 

I have no idea if the VVT does all that or what. All I know is the gearing is different. You know anyway to link to a secure web page?

 

Not that I know of. Even if you posted the link, we wouldn't have access to it. Only thing I can think of is taking a screen shot and hosting it in photobucket or something. But I believe you, it's just weird.

 

I am SOOO gonna help you right now. I looked into this issue when the car was first released. Here ya go:

The different final drive ratios are for the MANUAL transmissions, NOT the automatics. While GM does have different PART numbers for the auto in the SS vs. the LS, they are in fact the exact same 4T45E automatics with the exact same final drive ratio.

Now, if you wanted a different final drive ratio, you accomplish that via a differential swap. The differential determines the final drive ratio.

If you actually want to do that, get in touch with Engineered Performance. They make Limited Slip differentials for GM automatic transmissions. I have one.

As far tuning, HP Tuners does already support our Transmission Control Modules (TCM). However, they don't support the 2005-06 ECM's in the L61 cars. So you probably wouldn't be able to use it yet. Nobody has tried my knowledge yet.

Was there anything else I could help with?

 

Yes the trannies are different. For all the GM guys pick a cobalt in SI and find your RPO code selections, theres actually about 5 different final drives for the transmissions.

 

Halfcent I'm looking at the 2 different automatic transmissions listed in my parts computer right now! They have 2 different part #s and cost different prices. Do you have any idea how to link to a secure web page? If so I can show everyone.