73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => 4 Wheel Drives => Topic started by: Bobs85PU on March 14, 2012, 06:35:06 am
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Recently, I obtained a 1980, 3/4T 4x4.
This is only the second Chevy Pickup I've owned, that I'm going to have to "build" back to highway condition.
I viewed a number of posts about transmission and Transfer Cases and am totally confused...I have no idea what components are present in my truck's drive line...Other than it has a manual floor shift transmission and manual transfer case...It also has locking hubs.
As this vehicle has sat unused for a number of years, I want to go through the drive line and replace all gaskets and seals, as it has been my experience that once I start driving the truck, every gasket and seal will start leaking...besides, I'd like to ensure the components are usable, or in need of a rebuild.
Right now, I feel I'm in over my head, but with the help of a year specific Service Manual and help from members of this website, I'll overcome my ignorance and the learning curve, and have a dependable vehicle when I'm done.
Here's a picture of the Transmission and Transfer Case:
(http://i89.photobucket.com/albums/k217/bgeshel/DSCN0710.jpg)
By the by, the original cab was burned in an electrical fire...So, I have a real do-it-yourself project on my hands!!! :-\
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The transmission is a Muncie SM465. It is a 4 speed with a compound first gear (gearing: 6.55, 3.58, 1.70, 1.00, 6.09R). First gear is unsynchronized, but the rest do have synchros.
The transfer case looks to be a NP 205 due to what looks like the 'figure 8' adapter pattern.
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Yup. SM465/NP205.
The strongest combo available for our squarebodys. :)
Should have a GM Corporate 10-bolt front axle, and the GM Corporate 14-bolt, 10.5", full float rear axle.
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Welcome to the site.
The SM465/NP205 you have are a very stout combination.
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Yup. SM465/NP205.
The strongest combo available for our squarebodys. :)
Should have a GM Corporate 10-bolt front axle, and the GM Corporate 14-bolt, 10.5", full float rear axle.
It looks like that's what I have!!! Here's some pics:
Front manual hubs:
(http://i89.photobucket.com/albums/k217/bgeshel/DSCN0717.jpg)
10-bolt front axle:
(http://i89.photobucket.com/albums/k217/bgeshel/DSCN0718.jpg)
Rear axle end view:
(http://i89.photobucket.com/albums/k217/bgeshel/DSCN0719.jpg)
Rear axle:
(http://i89.photobucket.com/albums/k217/bgeshel/DSCN0720.jpg)
Another view of the Transfer Case:
(http://i89.photobucket.com/albums/k217/bgeshel/DSCN0709.jpg)
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Front axle is a Dana 44 with the factory Dana-Spicer locking hubs, Rear is a Corp. 14 Full Floater. If I had to guess you probably have 4.11 gears. As said you also have a NP205 transfer case and SM465 transmission. IIRC the transfer case is 1979-80 vintage due to the slip yoke of the 205. Someone will chime in if I am wrong.
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That's a 10-bolt F/A. No doubt about it.
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That's a 10-bolt F/A. No doubt about it.
Darn i posted too quick without looking. So should an 80 K20 have had a 44 and maybe someone swapped it out?
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i think 80 was the changing year where the early trucks got 44s while the new trucks got 10s
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If your '80 has a D44 then it was a swap.
Up to 1978, 1/2, 3/4 trucks had the D44. 1979~1987(91) had the 10-bolt.
Additionally, all 1980 4x4 trucks had the NP205, with spicer lockouts.
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lol i was off by a couple years but it could still be around in other stock setups
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Its a good drive train not the best or worst we don't know what gear ratio you have but no problem using 33 inch tires and with 10 bolt front axle 36 inch max if you run an open diff
maybe 38's light foot
I have a friend that runs 38's with 1/2 tone axles and when it brakes he pays to have it fixed