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2008 Impala LT 3.5L V6
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Discussion Starter · #1 ·
Can I put a 2007 terraza transmission into a 2008 impala. The transmission just went out on my Impala and I have a 2007 terraza sitting around. I was wondering if the transmission from the terraza would fir into the impala?
 

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2008 Impala LT 3.5L V6
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Discussion Starter · #7 ·
Just looked it up. Assuming you have the 3.9 They both have 4T65 transmissions but in different configurations. They may marry up and you'll have a drivable car but odds are, it won't feel right at best. You might want to talk to a transmission specialist instead.
My impala is a 3.5 and the Buick is a 3.9. Would that make a difference at all?
 

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2009 Impala SS
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As far as I can tell, there's a good chance they are different. Not so much in the overall transmission but they probably have totally different valve bodies to shift at different points.
The 4T65E shift points are controlled by the TCM via the shift solenoids, TCC solenoid, and pressure control solenoid. The difference, if there is one, is likely the final drive differential ratio.

Several folks have swapped 3.9L to 3.5L engines and the converse. They use the same block casting.

EDIT
The Impala has a 3.29:1 final drive ratio.
The Terazza can have 3.29:1 or 3.69:1 final drive ratio. Check the SPID.

You'll need to mod the Impala TCM programming for the 3.69:1 final drive ratio with the Impala tire sizes. That's the easy part. HP Tuners can do it.
You'll also need to re-code the ABS controller for the modified final drive ratio. That's the sticky wicket. I believe it can be done with a Tech2
 

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2008 Impala LT 3.5L V6
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Discussion Starter · #10 ·
The 4T65E shift points are controlled by the TCM via the shift solenoids, TCC solenoid, and pressure control solenoid. The difference, if there is one, is likely the final drive differential ratio.

Several folks have swapped 3.9L to 3.5L engines and the converse. They use the same block casting.
So it's likely it can be swapped? If so, does it need to be reprogrammed?
 

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2009 Impala SS
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So it's likely it can be swapped? If so, does it need to be reprogrammed?
See my edit in my post. Yes. You can re-code the TCM.

Check the transmission RPO on the SPID sticker in your donor chassis. M76 is 3.69:1 M15 is 3.29:1 If it's an M15 4T56E you don't need to do anything but bolt it in and go.
 
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