Newb question on t case retrofit

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chaosrob

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I have a 87 V10 with a 700r4 and a 208 t case. I am getting ready to swap the 5.7 TBI out for a 6.0 and am keeping the 700r4 in it until spring. In the spring I will be swapping the 700r4 out for a 6l80e. My issue is it does not appear that anyone makes an adapter for the 6l80e to 208 t case but they do for the 6l80e to 205. If I were to swap out the 208 in favor of the 205 would I have to do anything special with the shifter for the t case or could I use the same mechanism that is currently there for the 208?

I am sure this would become pretty clear while performing the work but since I have not done it yet I thought I would pick the minds of those on the site who may have knowledge of the swap already. TIS
 

climb-101

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i would do the 205 and twin stick it. it run off a cable when you do that
 

dvdswan

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definitely do the 205.
 

rpcraft

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You can use the adpater from a 4l80e to an NP208 from what I understand. I think the only difference is if you are using a 2wd 6l80E you just have to trim the output shaft shorter (I think its a 5/8 cut on the shaft). The NP205 does not have as low as crawl ratio as the np208 but a lot of folks insist to have it because it is technically stronger. There's been plenty of 3/4 and one ton trucks with a th400 and np208 though so you do have choices.
 

PrairieDrifter

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Youll most likely need a later 205 from the 80’s to be able to mate up to a 4l60, might have to change some input and output shafts as well I’m not sure though. Could get pretty tricky, you’ll have to make sure you have the same adapter as the crossmember you have, there’s a short and a long foot adapter, the later 80’s would be a short foot and have a kind of “w” crossmember.

As far as I know the 208 shifter mechanism will not work, mainly because the mechanism for the 205 is mounted to the transfer case itself and to the adapter to the trans. Also gonna have to change driveshafts and possibly yokes, as well as the 205 has a different support brace. A couple other small things like speedo sensor and 4wd indicator light and that stuff.

Pretty big project lol not impossible though just not fast and easy.
 

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