I Have A C5 And Would Like To Swap The 4 Gear Auto Tranny
For A C6 Paddle Shift 6 Gear Auto Tranny. Anyone Ever Done This. Is It A Bolt On Switch Or Even Possible?

 

Yep you and me both and a whole bunch of A4 owners would love to swop the parts needed are cost prohibitive and you and I should just buy a C6 Problem is I love my C5. Check it out things may have changed since I searched it out. The generations are on a different language the physical compatibility is there it can be done but mucho dollars how many dollars?? Lots

 

$$ and time solve most things

not sure if RPM has done this, I know they have installed the A6 in C6Z's

 

Anything is possible with enough $$$$$$$ ....

Problem is it would probably cost more to install the A6 in a C5 than buying a brand new C6 ... so .... no ..... it hasn't been done.

Here's the problem .... even assuming the A6 would fit, and you figured out how to mount the paddles ..... the PCM in your C5 has no clue how to manage a 6 speed automatic ... it only knows about a 4 speed. So you have to figure out how to get a C6 PCM into your C5. Putting aside the issues of how a C6 PCM would control an LS1/LS6 engine .... the C6 PCM uses a new network technology called "CAN" and it uses that network to interface with the BCM. On start, the BCM passes the PCM a "fuel enable" password if the BCM is sure the vehicle is not being stolen .... so now we need to put a C6 BCM in the car .... but a C6 has completely different systems for "starting" the car ..... it is a "keyless" system, and door locks and controls are completely different (there is no mechanical door handle on a C6, opening a door is an electrical function) .... so now we have to get the C6 BCM to talk with our C5 computers such as the RFA and the DCMs .....

You're starting to get the picture ..... basically you'd have to completely re-wire a C5 so electrically it is a C6 ...... and do it so the C6 computers aren't throwing codes when they perform tests for functions available in a C6 that aren't in a C5, such as the electric door handles.

Save your money ... you want a 6 speed auto ..... buy a C6.