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93 GP SE 3.1 4T60E - Will 99 Silhouette 4T65E work?

ktmccrary

New member
My 93 Grand Prix 3.1 seems to have popped the transmission band (4T60E) and will not shift out of 1st. It has 225K on it and has had a popping in the tranny ever since 60k miles. My 99 Olds Silhouette has a blown 3.4 engine with a 4T65E tranny in it. I have both complete vehicles, so can exchange whatever is necessary.

Question: What will I need to know to put the 4T65E in place of the 4T60E? From my limited knowledge and research it appears that I will need to swap the PCM from the Olds to the Pontiac and well as the wiring harness.

Will the 4T65E from the 3.4 engine mount correctly to the 3.1 engine and will it mount correctly to the 93 GP SE carriage? Do the CV joints need to be swapped as well? Is there anything else that needs to be swapped, or anything else I need to know to accomplish this. Does the PCM need to be tuned to the new vehicle, etc? I do understand that the vacuum modulator is eliminated with the 4T65E and the PCM and harness take care of this issue.

Any and all advise is appreciated --- EXPERT advise is ESPECIALLY appreciated. Thank you in advance.
 


You will definitely need to swap the harness, I don't think there is anyway to get around doing an obd 2 conversion. The 3800 luminas and monte carlos came with the 4T65e and still used the old gen 1 knuckles and hubs so you may be able to use those half shafts. I can't speak for mounting, as i honestly have no idea on the silhouettes, however it might not hurt to look at the montes or Luminas again for brackets and mounts.
 
I should specify the 98 & 99 (maybe others as well, not sure how many years the L36 was an option) Luminas and Monte Carlos before the new Monte bodystyle.
 
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