Author Topic: Automatic transmission floor tunnel  (Read 1789 times)

Offline BradRuiz 83

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Automatic transmission floor tunnel
« on: December 27, 2019, 06:24:07 PM »
I am converting a 73 gmc truck that is 2 wheel drive  into a 4x4 and need to change out the transmission floor tunnel... I  will be installing a automatic transmission with a NP208. Has anyone done this before.  I just purchased a floor hump on Ebay.  Anything helps... Thanks

Offline Captain Swampy

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Re: Automatic transmission floor tunnel
« Reply #1 on: December 28, 2019, 09:28:40 PM »
You should be able to see the line stamped in the floor where you need to cut. The pan will bolt in.
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


http://forum.73-87chevytrucks.com/smforum/index.php?topic=32209.0

Offline BradRuiz 83

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Re: Automatic transmission floor tunnel
« Reply #2 on: January 04, 2020, 07:22:39 PM »
I have a 73 gmc 2 wheel drive and I am going to convert it to 4x4... the truck is an original automatic truck and I just purchased a 4x4 trans tunnel of a 77 Chevy truck that was also a automatic and had a NP203 transfer case.  My problem is I mocked up the 4x4 tunnel on to the floor of my73 gmc, and I have a 4 to 5 inch gap. I might be needing another section to the floor or what are my options... has anyone done this before....

Offline zieg85

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    • 73-87 GM squarebody extended cab and conversions up to 91 R/V series
Re: Automatic transmission floor tunnel
« Reply #3 on: January 05, 2020, 07:26:06 AM »
The trans tunnel should be very similar between 2 and 4 wheel drives in automatics as far as height.  Obviously the 4 wheel drive has provisions for the transfer case selector.  Further back under the seat is where the big difference in the cab floor.  You will need to find a donor floor to get what you need.  This may help  http://forum.73-87chevytrucks.com/smforum/index.php?topic=25239.0
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline BradRuiz 83

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Transfer case shifter
« Reply #4 on: January 18, 2020, 09:09:19 PM »
Will a 203 shifter assembly work on a 205