14 bolt semi float factory locker

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bucket

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Now I see the confusion.

Your door plate mentions camper loading, but it’s not a camper special truck. Camper Special chassis package is option Z81, and it’s only for 3/4 ton (or bigger) trucks. IIRC my data plate lists GVWR of 8400, axle loading, and then a max camper weight of 2650 lbs. The wide band around the back and side of the cab also has camper emblems that look like a teepee, and the logo under it says Camper Special 8400 GVW.

For those who want more info - A factory camper special also has special chassis tie towns in several places. One on each front fender under the windshield, and one on each back cab corner with a bracket that extended through the front of the box. The system seemed to tie the box and the cab together with the camper. The camper connected to the cab brackets with some type of shock absorber.

Bruce

Not all Camper Specials had those brackets. They were an additional option.
 

Craig 85

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Does a 4wd 1/2 ton with a long bed and a 400 seem... unusual?

I had a '77 K5 that had a 400 with HD emissions and ran on regular fuel. GVW was 6200 LBS.
 

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So gov lock, g80, could remain functional by not flooring it when stuck? So gently accelerating out?
 

77 K20

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So gov lock, g80, could remain functional by not flooring it when stuck? So gently accelerating out?


I would say yes. I had a G80 in my S-10 ZR2 and drove it like an adult while off-roading. Never had an issue. Also my 2003 Silverado 2500 with a 8.1L engine had the G80 and once again, no issues.

Now if you try to put 33" tires or something larger on it then maybe you will stress it out too much and it will break.

How often do you think it would even engage with your driving style/area? For a lot of people it will probably never even engage unless you live somewhere where you get snow/ice in winter. Or unless you take it off road.

Heavy throttle when trying to get unstuck or thru something will often result in destruction not matter what you have. I blew up a Powertrax Lock Rite and most of my 12 bolt differential in my old '77 K10. I was in my early 20's and apparently my right foot was a lot heavier back then.
 

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I would say yes. I had a G80 in my S-10 ZR2 and drove it like an adult while off-roading. Never had an issue. Also my 2003 Silverado 2500 with a 8.1L engine had the G80 and once again, no issues.

Now if you try to put 33" tires or something larger on it then maybe you will stress it out too much and it will break.

How often do you think it would even engage with your driving style/area? For a lot of people it will probably never even engage unless you live somewhere where you get snow/ice in winter. Or unless you take it off road.

Heavy throttle when trying to get unstuck or thru something will often result in destruction not matter what you have. I blew up a Powertrax Lock Rite and most of my 12 bolt differential in my old '77 K10. I was in my early 20's and apparently my right foot was a lot heavier back then.

I frequently get stuck on my own yard with my 1996 f150. Although, the tires are goodyear Wrangler with a very basic, bidirectional, non aggressive tread. I was gonna get some Cooper AT3 which can handle water much better. Any amount of mud or grass and it's stuck essentially. Only when pulling weight does it get grip. I think 770 pounds of sand in bed was necessary to get up my driveway in winter time at a 35 degree angle or so(not sure what grade that would be) with a headstart and less than 40% ice.
 

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Locking would be cool because if I know it can and will engage then no need to try to floor it through everything.
 

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So gov lock, g80, could remain functional by not flooring it when stuck? So gently accelerating out?
Kinda good for a snowy road. Not an off road traction device at all.
The 9.5 semi-float axle is a bit of a useless heap compared the 14 bolt 10.5.
 

Rusty Nail

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Bruce is right on up there...some year it changed from Big10 to Heavy Half but was the same stuff rebadged OR some similar things.
Changed with converters and pumps.

Half ton frames- with moar sprang and thangs
Stuff

3/4 ton frames are way better imo.
They are taller and wider and thicker
Whatever.
Especially old enough before they got nuked for converters or whatever happened specifically to half ton FRAMES.
Big differences after '77? Right in there with the frames and stuff...thangs.

Camper Loading is just how D.O.T. taxes vehicles by weight rating also...
Basically.

If you have a 4.10 14 bolt positrac axle and ... you wanna put it in the best Square you got because it's fixin to be the good truck.
Lololo

That is what you want!!
:pedobear:

Word up.

Bolt it in!

It's not much problem outside of the fact of it's heavier than a mother .
You already own almost everything you need to :grd:

*In addendum
I dont believe it is reasonable to build a 1/2 ton frame if a 3/4 ton frame was an option. No contest but I'm not certain 3/4 frame changes but it wasnt until later model rounded line or maybe not. Half tons was 78 or 79?
Whatever, that difference could potentially change my mind but I doubt it.

Somebody else knows wtf I'm babbling about I bet.
I'd build an entire truck around that Full Float differential.

:waytogo:

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AuroraGirl

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Bruce is right on up there...some year it changed from Big10 to Heavy Half but was the same stuff rebadged OR some similar things.
Changed with converters and pumps.

Half ton frames- with moar sprang and thangs
Stuff

3/4 ton frames are way better imo.
They are taller and wider and thicker
Whatever.
Especially old enough before they got nuked for converters or whatever happened specifically to half ton FRAMES.
Big differences after '77? Right in there with the frames and stuff...thangs.

Camper Loading is just how D.O.T. taxes vehicles by weight rating also...
Basically.

If you have a 4.10 14 bolt positrac axle and ... you wanna put it in the best Square you got because it's fixin to be the good truck.
Lololo

That is what you want!!
:pedobear:

Word up.

Bolt it in!

It's not much problem outside of the fact of it's heavier than a mother .
You already own almost everything you need to :grd:

*In addendum
I dont believe it is reasonable to build a 1/2 ton frame if a 3/4 ton frame was an option. No contest but I'm not certain 3/4 frame changes but it wasnt until later model rounded line or maybe not. Half tons was 78 or 79?
Whatever, that difference could potentially change my mind but I doubt it.

Somebody else knows wtf I'm babbling about I bet.
I'd build an entire truck around that Full Float differential.

:waytogo:

You must be registered for see images attach
I think I got most of what you are saying. You think that even a light duty application a 3/4 ton frame with softer springs and less aggressive everything be superior to a 1/2 ton frame? Im curious to your thoughts. The 1/2 ton frame has this going:

The entire drive line is there, literally(minus front drive shaft) and the only thing I would have to do is build the cab up "around" it(heavy amount of work if it wasnt obvious) and drop a motor in. Trans is still in... but its been sitting for 20 years now. Rebuild? Its automatic. Assuming a th400 if it came with towing package and a 400 sbc. Is there an easy way to tell a th400 from a th350? maybe its not a th at all? I can post a pic.

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75gmck25

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Check the pan shape to determine if it’s a TH400, but don’t worry if it’s a TH350. My 8400 lb GVW ‘75 K25 came with a TH350 (stock) and it has held up very well.

Just google “TH400 pan shape” to see multiple references with pictures.

Bruce
 

Rusty Nail

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I think I got most of what you are saying. You think that even a light duty application a 3/4 ton frame with softer springs and less aggressive everything be superior to a 1/2 ton frame? Im curious to your thoughts.

You must be registered for see images attach


Ohh weee ! That almost seems like a trick question!
But yes.
Almost 100% certain that I would not begin to consider building a half ton if I could avoid it.
Judging from the pix? No cab in the way?
No brainer :imo: 3/4 frames/trucks are superior to half tons in almost all cases.
Even bolting "half ton stuff" onto a 3/4 ton frame yields a better result.
Sure mugs will argue about the required work and stuff but that reality wont change.
Yet a 3/4 is maybe OVERKILL for your unknown intended functions but if you gotta do it ALL anyway, that's my opinion - thanks and good luck!

I would not have had initial interest in MY '77 were it a half ton - wouldn't have brought it home much less looked twice. Everybody gots one of them deals...they're all junk lol.
:pokeowned:
A 20 is the draw for sure.
"Oh! It's 20? That's fvcking hot. :flowers2:Those are Niiiice..." Those are more expensive because they have more worth. Exponentially stronger.

Dont like oussy assed half ton trucks, what can I say? Housing a natural aversion towards 10s. Not for me..ESPECIALLY a 2wd 10,were that the case.. You got a chance to switch and I feel it my responsibility to encourage you, Miss.
:waytogo:

For sure rebuild a 20 year old turbo 350 sitting there, if it were a th400 I'd say run it, its probably alright.. LoL.

Maybe I dont understand.. You can build one not as good or you could build one that is better... :shrug:you got a bunch of really cool parts. Hella potential layin about! Lotta monies' worth..
 
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75gmck25

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In the past folks have said that only the 1 ton frame is heavier steel - 1/2 and 3/4 are the same, but I’ve never actually checked.

One feature on some 3/4 tons and 1 tons was a 56” long rear spring instead of 52”. For the same GVW rating, it has more flex and a better ride.

I know my K25 has 52” HD 7 leaf springs (rated at 2775 lbs per spring), and it doesn’t begin to ride smoothly until you have about 1000 lbs in the bed. However, you can also load 3000 lbs in the bed and there is almost no change in height. Very useful when you need to pick up a pallet of cinder blocks or a couple yards of fill material.

Bruce
 

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In the past folks have said that only the 1 ton frame is heavier steel - 1/2 and 3/4 are the same, but I’ve never actually checked.

Since you asked:

1/2 ton C frame section modulus 3.10
1/2 ton K SWB frame section modulus 3.14
1/2 ton K LWB frame section modulus 3.88
3/4 ton C frame section modulus 3.57
3/4 ton K frame section modulus 3.88
3/4 ton C/K C6P (8,500+ GVW) section modulus 4.53
3/4 ton crew cab section modulus 7.33
1 ton C/K frame section modulus 6.14
1 ton C/K crew cab section modulus 7.33

All use the same grade of 36,000 to 39,000 lb steel. So the difference is in frame height and material gauge.

*Section modulus: The moment carrying capacity of an object is directly dependent on geometrical property (I) and material property (E) of an object, which is collectively termed as flexural rigidity(EI).Geometry of an object plays an important role in load bearing capacity of an object which is indicated by moment of inertia of a section.

Hope that clears things up. :rolleyes:
 

bucket

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Since you asked:

1/2 ton C frame section modulus 3.10
1/2 ton K SWB frame section modulus 3.14
1/2 ton K LWB frame section modulus 3.88
3/4 ton C frame section modulus 3.57
3/4 ton K frame section modulus 3.88
3/4 ton C/K C6P (8,500+ GVW) section modulus 4.53
3/4 ton crew cab section modulus 7.33
1 ton C/K frame section modulus 6.14
1 ton C/K crew cab section modulus 7.33

All use the same grade of 36,000 to 39,000 lb steel. So the difference is in frame height and material gauge.

*Section modulus: The moment carrying capacity of an object is directly dependent on geometrical property (I) and material property (E) of an object, which is collectively termed as flexural rigidity(EI).Geometry of an object plays an important role in load bearing capacity of an object which is indicated by moment of inertia of a section.

Hope that clears things up. :rolleyes:

I believe that also varied a bit here and there, throughout the production run.
 

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I got that from the 1985 book.
I believe that also varied a bit here and there, throughout the production run.

Probably. I got that from the 1985 specs.
 
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