# What Are These Axles??



## thomason_45 (Nov 28, 2005)

I have an 82 chevy c20 3/4 ton 4x4.

The front axle is a 10 bolt and the rear axle is a 14bolt.
I was just wondering what the right names for these axles are?


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## Detroitdan (Aug 15, 2005)

Well, first of all if it is 4x4 then it is a K20 not a C20. Your front differential should be a Dana 44, same as was used in the half ton except for beefed up axleshafts and 8 lug hubs with bigger brakes. Very good axle, will need to keep an eye on the axleshaft u-joints. Your rear axle is a 14 bolt Corporate, in 82 it may have been either a full floater or a semi-floater, either one is real strong, and far better than the Dana 70 that was in the back of some early 1 tons. The 14 bolt corporate full floater is the same axle as is under a 1 ton, only difference being spring perches are in a different spot, and the DRW trucks had different brake drums to allow for the Budd wheels. The full floater is supposed to be much stronger, PITA to get at the brakes though, because you have to unbolt and remove the axleshaft before you can get the drum off. The semi-floater does not have bolt in axles, instead they are held in at the differential end by c-clips. I have heard bad things about the c-clips breaking, but I ran 35s and plowed (not w/35s on) for years with an 81 semi-floater with 4:10s and a Detroit locker, never had a bit of trouble. I think all the horror stories come from guys turning 44s with a big block, and beating on it. All you have to do to tell is look at the center of the hub, if it has a raised area with 8 bolts (not the lugnuts!) it is a full floater. The word "floater" is supposed to have something to do with the way the weight is distributed over the bearing and hub rather than the axle.

Cool looking truck, by the way. In my opinion that is the best plow truck there ever was. The shortbeds and Blazers had some advantages when it comes to wheelbase, but you couldn't get a short wheelbase with 3/4 axles, and in my opinion the half ton stuff just doesnt take the abuse like a 3/4.


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## Joe D (Oct 2, 2005)

Anything after 80 should have the 10 bolt. In the 8 lug trucks like the K20 it used diffent knuckles and had larger brakes. The rear is a 14b 9.5 in axle. It's a good axle just not for the hardcore.


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## derekbroerse (Mar 6, 2004)

Detroitdan said:


> Well, first of all if it is 4x4 then it is a K20 not a C20. Your front differential should be a Dana 44, same as was used in the half ton except for beefed up axleshafts and 8 lug hubs with bigger brakes. Very good axle, will need to keep an eye on the axleshaft u-joints. Your rear axle is a 14 bolt Corporate, in 82 it may have been either a full floater or a semi-floater, either one is real strong, and far better than the Dana 70 that was in the back of some early 1 tons. The 14 bolt corporate full floater is the same axle as is under a 1 ton, only difference being spring perches are in a different spot, and the DRW trucks had different brake drums to allow for the Budd wheels. The full floater is supposed to be much stronger, PITA to get at the brakes though, because you have to unbolt and remove the axleshaft before you can get the drum off. The semi-floater does not have bolt in axles, instead they are held in at the differential end by c-clips. I have heard bad things about the c-clips breaking, but I ran 35s and plowed (not w/35s on) for years with an 81 semi-floater with 4:10s and a Detroit locker, never had a bit of trouble. I think all the horror stories come from guys turning 44s with a big block, and beating on it. All you have to do to tell is look at the center of the hub, if it has a raised area with 8 bolts (not the lugnuts!) it is a full floater. The word "floater" is supposed to have something to do with the way the weight is distributed over the bearing and hub rather than the axle.
> 
> Cool looking truck, by the way. In my opinion that is the best plow truck there ever was. The shortbeds and Blazers had some advantages when it comes to wheelbase, but you couldn't get a short wheelbase with 3/4 axles, and in my opinion the half ton stuff just doesnt take the abuse like a 3/4.


It will be a corporate 10 bolt. Late 70's they still seemed to use some of each, but by then they should all be GM axles. Basically the same axle as a Dana 44 (in terms of strength)

Not so sure about spring perches being in different places, but the axles are different widths. Pretty sure I can run the dual wheels on any axle I want, we even mocked them up on a Jimmy one time just for fun...

I was also under the impression that the Dana 70 was the stronger axle over the 14 bolt. It is certainly a bigger, beefier axle (appearance-wise). They were mainly used in the 1-ton pickups (with the flared fenders) and were the widest.


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## Joe D (Oct 2, 2005)

The dana 70 is a great axle, like the 10.5 ff 14 b. The 14b is limitied by max of 5.13 gears and locker selection. The 70 has more available for it. 
I think ultimatly the 14b is stronger though, larger axle shafts, pinion support bearing and larger gear


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## Detroitdan (Aug 15, 2005)

I just remember the local GM truck guru telling me the Dana 70s had too many problems and he much preferred the 14 bolt full floater. I have run both with 35s and also plowed and couldn't break either one. I guess I remember hearing the 10 bolt fronts being referred to as corporates, I just always think of it as a Dana 44. My trucks usually had donor axles from who knows what year, so I might have had anything. My 79 1/2 ton got 3/4 ton axles, and the rear 14 bolt FF had different drums that would allow the use of dual wheels. My 81 3/4 had the 9.5 14 bolt semi, and it wouldn't take a dually wheel. I just recently had an 84 3/4 with a semi-floater, I actually tried to fit one of my dually wheels and it wouldn't go on. But the rear end I put in the 79 I removed from a 3/4 single wheel, and it bolted right in. The drw 1 ton 14 bolt is the same width as a srw, the one that is different is for a DRW pickup as opposed to a dump chassis. Idon't remember where I got the info about the perches being different, the leaf springs are still on the outside of the frame. Maybe it was the shock mounts I was thinking of. They were inside the frame on 1-tons and outside on 3/4 tons. Thanks for straightening me out.


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## thomason_45 (Nov 28, 2005)

Thanks for the info guys... i just got this truck and im tryin to figure out all the specs on it... i got the c20 info from inside the glove box..... this truck was assembled so the cab must have been from a c20 but the truck was a k20.....anyways thanks again


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## derekbroerse (Mar 6, 2004)

Just to clarify... Dana 44 and Corporate 10 Bolt are NOT the same axle. The Corp axle is a regular Chevy 10 bolt, same as a rear axle, with the steering added. Made in-house at GM.

The Dana is an outsourced piece used in the earlier trucks.


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