Squarebody Differentials.

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Honky Kong jr

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A 307 cu in version was produced from 1968 through 1973. Engine bore was 3.875 inches with a 3.25-inch (82.6 mm) stroke. All 307s had large 2.45 in (62.23 mm) journals - the crankshaft is sourced from the 327. Pistons used with the 307 share the same pin height as the 327 but retaining the 283s bore size (prior to 1968 it was possible to stroke a 283 into a 307 where aftermarket pistons had to be used). This engine was also used by Holden in Australia and by General Motors' South African arm.
 

bucket

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I don’t think so after further digging no 307was 327 stroke 283 bore. 302 was 327 bore 283 stroke

Right. The 307 was the replacement for the 283. And it was used in the '68 full size cars too, but by '69 the standard V8 for those was the 2bbl 327.
 

Honky Kong jr

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Right. The 307 was the replacement for the 283. And it was used in the '68 full size cars too, but by '69 the standard V8 for those was the 2bbl 327.
The 283 was way better then the 307 imo
 
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bucket

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The 283 was way better then the 307 imo

I've got no gripes with the 307, or any small block really. They all served their intended purpose well. I will say the 283 ran as smooth as a sewing machine though.
 
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Honky Kong jr

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I've got no gripes with the 307, or any small block really. They all served their intended purpose well. I will say the 283 ran as smooth as a sewing machine though.
And they took a licken too.
 

78C10BigTen

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Anyone interested and close, I have a 10 bolt 3.08 Peg legger for $100, and a 12 Bolt 3.08 likely a peg legger, don't know for sure yet for $125. Drum to Drum on both, and all E brake cables are there. When I pull stuff, I don't butcher it like some people do.
Wish u were closer, i need that 12 bolt
 

78C10BigTen

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Not a dumb question. It's GM Corporate. Meaning GM made their own. It's not a Dana brand, or Eaton brand like other Truck manufactures use. Your 12 bolt will be a GM Corportate Truck rear end. Probably the best choice for a stock to mild performance powertrain on street tires.
If its GM's own axle and not an eaton isnt my g80 an eaton posi?
 

78C10BigTen

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My dad bought a 73 squarebody 2x with the 307, three-on-the-tree, manual steering. I learned how to drive in this baby.
I learned how to drive in a 73 also. A 250 straight 6, manual brakes and manual steering. Good memories.
 

Kim Burke

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307
A 307 cu in version was produced from 1968 through 1973. Engine bore was 3.875 inches with a 3.25-inch (82.6 mm) stroke. All 307s had large 2.45 in (62.23 mm) journals - the crankshaft is sourced from the 327. Pistons used with the 307 share the same pin height as the 327 but retaining the 283s bore size (prior to 1968 it was possible to stroke a 283 into a 307 where aftermarket pistons had to be used). This engine was also used by Holden in Australia and by General Motors' South African arm.

Replaced a 6cyl in an 81 Custom Deluxe C10. Built a bored(4.00”) 307 block, 327 Corvette rotator assembly, RV cam, and a cast iron intake w/2bbl Rochester. That engine was so durable(8yrs), responsive, and fun.
Everybody wanted to tell me it would run hot. Not. That truck went through a lot until I sold it in 91.
 

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FRONT DIFFERENTIALS
K10/K1500/K5 Blazer -Jimmy Front Differentials
1973-1976 Dana 44
1977-1978 Transition Years. Could be either Dana 44 or GM Corporate 10 Bolt
1979-1987 GM Corporate 10 Bolt (Thru 91 on K5 Blazer - Jimmy)

,
So my 79 k20 has a d44 front. You think its been swapped, or leftover from transition?
 

LateOnTheBrakes

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Sorry if it was covered in the last 30 pages of posts. Any chance of adding the fluid type and capacities to the original post?
 

Rusty Nail

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So my 79 k20 has a d44 front. You think its been swapped, or leftover from transition?


Nope.




AND!

Still wish I had a 307 crankshaft to play with..




Sorry if it was covered in the last 30 pages of posts. Any chance of adding the fluid type and capacities to the original post?

More than 2 quarts and less than 3.

Buy GL-5 fluid.
 

Cameron Covington

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Does anyone know if the Detroit locker came in the civilian full float 14 bolts or just the cucvs. My K30 is an 86 with a 454 all factory and original 88,000 miles and the rear diff cover has never been pulled. I know It either has 4:10’s or 4:56’s I’m just hoping and praying it’s not the gov lock. I’m going to pull the cover either Friday or Sunday, I’d just like to be disappointed before hand so that I’m not pissed off under the truck.


Sent from my iPhone using Tapatalk
 

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