4t65e trans swap

[scotty]

got a friend with a 2001 impala ls 3800. the transmission is gone except for 1st and reverse. the transmission is a 4t65e with a 2.80 gear ratio. the only 1 he can get at the scrappers came from a smashed up police car it has a 3.05 gear ratio and it is also a 2001 4t65e. can these transmission be exchanged without problems? cannot get any info from GM dealer. thanks in advance

ps was a regular here when i had my grand am with a 3100 but now i'm driving a 2007 charger and yes it does have a hemi and my blazer has a 4.3 vortex and my buick century has a 3300 90degree v6

[pocket-rocket]

It would swap over fine, but the speedo and stuff would be off, so the PCM would have to be told the new ratio by way of being reflashed.

[scotty]

thanks. i will let my friend know

[pocket-rocket]

If you don't know anyone in the area that has the equipment to do it, a dealership (other then the ones that didn't want to help) should be able to do it for you.

[gpse3400]

Actually the issue with the speedo being off will have to do with the tone wheel for the sensor. The amount of teeth on it will dictate indicated speed. This part is transferable.

[IsaacHayes]

The ECM will still need to be edited to correspond with the correct shift settings for the different gearing though.

[gpse3400]

The computer might detect a slip as the final drive is off but it should run fine. If you need it, I'd try to run with it. The differences are not great enough to stop you from driving it Shift timing and speedo accuracy also being minute.