Aisin Automatic Transmission shift kit?

[kevinthenerd]

I have an Aisin AF-23 automatic 5-speed in a 2003 Saturn ION. The transmission in these cars has always been one of the biggest complaints among its owners, and, given the performance difference between the Aisin 5-speed and the 4T-45E Hydramatic 4-speed in the 05+ models, it's obvious that the motor isn't what's holding this car down the most. (It's sad: Some sources are quoting 0-60 time differences on the order of 2 seconds.)

With all that said, I've seen "shift kits" throughout the Internet that promise quicker and more solid shifts, and, despite what I would think, better transmission reliability, but I've yet to find one for this particular transmission.

1. Where can I get such a kit for the Aisin AF-23?
2. Why would Aisin design a transmission with less-than-optimal reliability AND performance?
3. How does a shift kit actually work? What parts are replaced/improved?

[kevinthenerd]

If it's helpful to know, this isn't the transmission in the Chevrolet Cobalt, but I've heard that Aisin makes transmissions for various Japanese manufacturers.

[bluevp00]

If you really want better transmission performance from your car, then I'd suggest swaping out the automatic and dropping in a manual trans. If the automatic drops 0-60 times by almoast 2 seconds, then even an automatic with a shift kit will still be slower than the manual.

[kevinthenerd]

Originally Posted by bluevp00

If you really want better transmission performance from your car, then I'd suggest swaping out the automatic and dropping in a manual trans. If the automatic drops 0-60 times by almoast 2 seconds, then even an automatic with a shift kit will still be slower than the manual.

I think you misread the post. One automatic is 2 seconds faster than the other automatic. I'm not talking about the manual, which is faster than both.