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TH350/NP203 to 4l80E/205?

LoggieStyle

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I'm thinking about going to a 4l80E and NP205. I'm going to be doing the work myself, I'm not a skilled mechanic yet but I have help and I'm willing to learn and put hard work into it. My question is this, what needs to be done to get the 4l80E and 205 to mate properly? Also will I have to buy a 700 dollar adapter kit? or is there another way to handle this? Are there any other costly parts I may have overlooked needing other than the TCU?


Thanks,

Logan
 
i believe the 4l80 is totally computer controlled. it needs a vehicle speed sensor, a throttle position sensor, and its own computer. jet sells the computer package, but i cant get a price from anyone. its in their catalog, but no one stocks the thing. if you need a part number drop me a pm...next time im at work ill look it up.
ryan
 
4L80E/NP205 is stock equipment for a '91 crewcab... so you should be able to get a factory adapter from GM or a wrecking yard. The adapter itself is the same as a 85-90 TH400/NP205 adapter, with about 0.030" shaved off the shoulder that fits inside the back of the tranny.

The NP205 from a '91 is unique - it has an electronic speedo. The 4L80E is also controlled by the ECM. Might be a good idea to get the whole engine/tranny/t-case from a '91 crewcab.
 
thanks, I figured that was the case, but I wanted to be sure I know what I am looking before I start searching through the salvage yards.

Logan
 
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