1976 F100. Trans/drive shafts

Blairsville Ed

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I’m looking at a 1976 F100 Long bed truck.
The vin plate indicates the trans code as C and the rear axle as 12. I believe a C code trans is a 3 speed manual but this truck has a floor shift automatic trans, and it has a large diameter, aluminum , 1 piece drive shaft. The current owner does not know which trans is in it.
How do you identify the automatic trans and did the 1976 Long bed truck come with a 1 piece drive shaft?
 

bubba22349

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Yes a C Trans code is for a 3 speed manual 3.03. No 1970's F100's ever came stock with a floor shifted auto Trans so it's been swapped in the alumium drive shaft is another tip of this swap. The rear axle code 12 for a 1976 pickup is a 3:00 to 1 ratio 9 inch rear axle. All 1970's long bed pickups I ever worked on had a two piece drive shaft. Look about 2 to 3 foot behind the Trans yoke to see if there's still the extra cross member that is used for a two piece driveshaft. If you have a picture of the Trans or count the number of oil pan bolts to be able to ID the Trans.
 

Blairsville Ed

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I decided to pass on the truck. It would have needed the automatic transmission steering column and linkage and a 2 piece drive shaft to make it look correct plus a lot of body work, so I’ll keep looking for a candidate to restore.
I did see a 1966 with a 289. Was that an option in 1966?
It appears that the automatic transmissions that were put into the trucks were the C-4,C-6 and possibly a fmx. Any other transmissions?
 

bubba22349

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The 289 was never offered in any year of the Ford pick ups though many in huge numbers were swapped in by people and it's usally all done with factory parts so it dose look like it's an original option. The 1965 & 1966 F100's had a choose of the 240 & 300 Six'es or the 352 FE V8's and as for an Auto Trans they only got the cast iron Cruse O Matic / FMX for many years I think this was up to least to the end of the 1972's year models. The first SBF 302 V8 was offered in the last half of the 1969 F100 model year (and only in the 2 wheel drives).

As far as using a one piece drive shaft in a long bed pickup it can be done successfully in this way any driveshaft that over 6 feet long needs to be a larger diameter like 4 inchs this keeps the vibration down.
 

Blairsville Ed

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I located a 1977 F150
300 imco
G code trans
46J rear axle
looks like a Dana 44 axle
Why did Ford use their 9 inch and some Dana 44 axles?
 

bubba22349

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Not sure on the G code Trans but I think it's an FMX, yes a 46 Rear Axle code is a Dana 44 unit. The first F150's (1975 up) were built to get around some of the Emissions regulations back then that the F100's had, these requirements didn't apply to the heavyer duty trucks like the F250's and up. During that time of the first ones they were a true heavy duty 1/2 Ton with a gross vechical weight close to what some of the F250's. A F150 with their heavyer wieght fit them into that emissions loop hole and soon the F150's were becoming very popular so that the 1983 Bull Noise trucks were the last of the F100's. They also used the Dana 44 axle in the F150's because of the extra load carrying capacity of those trucks.
 

bubba22349

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There are severial ways, first there should be an ID Tag with code numbers on one bolt of the Servo cover usally on passenger side. You can also Count the number of oil pan bolts and or take a picture of the Trans oil pan or the compleate Trans.

Door Tag Info Decoded
1977 Ford F150, B code is a 300 Six, N this Truck was built in Norfolk, Va., Z 00821 this unit number looks to be a late near end of 1977 model year production, Trim Code AU 4 is a Ranger Cab with Styleside pickup box and Tan Vinyl interior, Trans Code G it might also be a C6 I know my father in laws and severial other 1979 & 1978's F150's that I worked on had the C6's in them, Axle code 46 is Dana 44 with 2.72 to 1 Ratio, Axle J is Twin I Beam front suspention with Power Steering. DSO 21 10 13 this number seems to indicate that this truck was special ordered maybe a fleet purchase for the Atlanta Ford Georgia sales market. Edited
 

bubba22349

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With the 300's low end torque and the auto Trans it should work fairly well and get decent MPG.
 

wallen7

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The 289 was never offered in any year of the Ford pick ups though many in huge numbers were swapped in by people and it's usally all done with factory parts so it dose look like it's an original option. The 1965 & 1966 F100's had a choose of the 240 & 300 Six'es or the 352 FE V8's and as for an Auto Trans they only got the cast iron Cruse O Matic / FMX for many years I think this was up to least to the end of the 1972's year models. The first SBF 302 V8 was offered in the last half of the 1969 F100 model year (and only in the 2 wheel drives).

As far as using a one piece drive shaft in a long bed pickup it can be done successfully in this way any driveshaft that over 6 feet long needs to be a larger diameter like 4 inchs this keeps the vibration down.
My 75 came with an FMX
 

wallen7

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Not sure on the G code Trans but I think it's an FMX, yes a 46 Rear Axle code is a Dana 44 unit. The first F150's (1975 up) were built to get around some of the Emissions regulations back then that the F100's had, these requirements didn't apply to the heavyer duty trucks like the F250's and up. During that time of the first ones they were a true heavy duty 1/2 Ton with a gross vechical weight close to what some of the F250's. A F150 with their heavyer wieght fit them into that emissions loop hole and soon the F150's were becoming very popular so that the 1983 Bull Noise trucks were the last of the F100's. They also used the Dana 44 axle in the F150's because of the extra load carrying capacity of those trucks.
I can't remember the years but if you ordered positraction (traction lock) it came with the Dana 44
 

Blairsville Ed

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Trans tag indicates a C-4 transmission and the BOM on the axle indicates a non limited slip standard axle.
I’ll be starting the restoration at the back end by pulling the bed and doing the spring bushings, brake cylinders, brake lines, axle bearings and rebuild the axle.
I see that the Dana case has to be spread a little to remove the carrier. I want to add a limited slip while it’s apart.
Has anyone rebuilt a Dana axle and added limited slip? 400234A3-0E90-4896-9BB7-0C7958B2091E.jpegDD4A51FA-E918-48DF-B1A1-2BE841E512E6.jpeg
 
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