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interchangeable transmissions

lance4682

New member
i have a 99 gt and am about to put a cammed l67 into i figured while its out i might as well change the trans as well being that it is high mileage .... my question is i am not finding alot of gtp part cars locally to me that dont have a high mile trans as well in the 97-03 range. just wondering if i can broaden my search by looking 04 and newer or at another 3800 equipped car (impala regal etc) or if some one knows a spot online where a good deal could be found ...i am a penny pincher.......any help would be appreciated
 


03+ wouldnt work for what you really want.

Anything 97-02 from a grand prix, regal, park ave ultra (s/c version), even a bonneville with the s/c option has a 4T65e HD tranny.
 
GT gear ratio's are 3.29

GTP gear ratio's are 2.93

I figured you'd be just going to a GTP trans and using a L67 computer with the swap. Either way it will require a tune once the motor and either trans is put in the car.
 
i meant with the ssei and regal gs and such if there ratios were different from a gtp.....also i just purchased a dhp tuner (have no idea how to use it yet) but i will figure it out and have a pcm from the l67 i bought
 
Anything that was supercharged is a 2.93.

If the motor was N/A and from a regal, park ave or a bonneville the gear ratio can vary. Some have 3.29, some have 3.05 and 2.86.
 


last stupid question would it work the same as a gtp where a 03 trans would be more sought after due to the hardened parts
 
It's really only the 4th gear hub/shaft that is better and the valve body has some minor changes.

An 03+ trans could work in a older pcm I guess, but you'd have to figure out what has to changed.
 
04+ trans work in the -03 cars. Use a 03 pcm and tune it for the newer style.

Just transfer the range selector switch to the new trans and speed sensor depending. The only other issue is the cooler lines as the new style uses the push and clip style and the (iirc) 99 and older have the threaded nut style. Just get lines for the newer style.
 
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