Chevy K20 Rear Axle

Having problems trying to find a locker for it.
Two questions; what is it, how to change it.

How to tell between a h052 and a h072? Sold to me as a 3/4 ton
truck, but armchair mechanics have told me it might be a 1-ton.
The VIN is for a 3/4 but the arguments are pretty strong. Seems
to be it has had some modifications to it. Lot's of trouble
determining brake drums, then more trouble finding a universal
for the drive shaft. The Tractech folks told me it is a h072
after seeing these pictures.

Whatever it is I will probably, not sure yet, swap it with a Dana
60. Never did this before and would like to avoid surprises.
Where/what is a good source of instructions for swapping a rear
axle. Maybe I should replace the springs while I am at it? Help
me avoid surprises or having a project that takes forever.

Pictures at:
http://www.geocities.com/magooasdf

FRONT DIFF
It has two sets of numbers on the case
front view, drivers side top C-31256
front view, drivers side bottom 44-5F

REAR DIFF
It has one set of numbers on the case
front view drivers side 3934635 but it
is not clear, it may be S931635
It might be an Eaton h072 1-ton
It should be an Eaton h052 3/4-ton

1971 Chevrolet K20
Fleetside long bed
3/4 ton pickup
4WD
350
4-speed manual transmission with granny gear
Manual hubs


All ideas appreciated.

Thanks,

Vic

I can't help you on the #'s but if you swap it, check your O.A. width, the
distance between the spring centers, size and number of splines on the input
shaft, or U-joint size, and brake line fitting size. Know all the
dimensions before you shop (or know someone who knows!)
LD

"asdf" <[email protected]> wrote in message
news:[email protected]...
> Having problems trying to find a locker for it.
> Two questions; what is it, how to change it.
>
> How to tell between a h052 and a h072? Sold to me as a 3/4 ton
> truck, but armchair mechanics have told me it might be a 1-ton.
> The VIN is for a 3/4 but the arguments are pretty strong. Seems
> to be it has had some modifications to it. Lot's of trouble
> determining brake drums, then more trouble finding a universal
> for the drive shaft. The Tractech folks told me it is a h072
> after seeing these pictures.
>
> Whatever it is I will probably, not sure yet, swap it with a Dana
> 60. Never did this before and would like to avoid surprises.
> Where/what is a good source of instructions for swapping a rear
> axle. Maybe I should replace the springs while I am at it? Help
> me avoid surprises or having a project that takes forever.
>
> Pictures at:
> http://www.geocities.com/magooasdf
>
> FRONT DIFF
> It has two sets of numbers on the case
> front view, drivers side top C-31256
> front view, drivers side bottom 44-5F
>
> REAR DIFF
> It has one set of numbers on the case
> front view drivers side 3934635 but it
> is not clear, it may be S931635
> It might be an Eaton h072 1-ton
> It should be an Eaton h052 3/4-ton
>
> 1971 Chevrolet K20
> Fleetside long bed
> 3/4 ton pickup
> 4WD
> 350
> 4-speed manual transmission with granny gear
> Manual hubs
>
>
> All ideas appreciated.
>
> Thanks,
>
> Vic
>
>
>

Without researching too hard i can tell you that the front diff is a Dana 44
and
I'd swear up n down that's a Corporate 10 bolt n the back.
--
Mad-Dog
'79 Chevy K-10
Slightly modified
http://mad-dog16.tripod.com/

"asdf" <[email protected]> wrote in message
news:[email protected]...
> Having problems trying to find a locker for it.
> Two questions; what is it, how to change it.
>
> How to tell between a h052 and a h072? Sold to me as a 3/4 ton
> truck, but armchair mechanics have told me it might be a 1-ton.
> The VIN is for a 3/4 but the arguments are pretty strong. Seems
> to be it has had some modifications to it. Lot's of trouble
> determining brake drums, then more trouble finding a universal
> for the drive shaft. The Tractech folks told me it is a h072
> after seeing these pictures.
>
> Whatever it is I will probably, not sure yet, swap it with a Dana
> 60. Never did this before and would like to avoid surprises.
> Where/what is a good source of instructions for swapping a rear
> axle. Maybe I should replace the springs while I am at it? Help
> me avoid surprises or having a project that takes forever.
>
> Pictures at:
> http://www.geocities.com/magooasdf
>
> FRONT DIFF
> It has two sets of numbers on the case
> front view, drivers side top C-31256
> front view, drivers side bottom 44-5F
>
> REAR DIFF
> It has one set of numbers on the case
> front view drivers side 3934635 but it
> is not clear, it may be S931635
> It might be an Eaton h072 1-ton
> It should be an Eaton h052 3/4-ton
>
> 1971 Chevrolet K20
> Fleetside long bed
> 3/4 ton pickup
> 4WD
> 350
> 4-speed manual transmission with granny gear
> Manual hubs
>
>
> All ideas appreciated.
>
> Thanks,
>
> Vic
>
>
>

On Thu, 24 Feb 2005 13:18:55 -0500, "Mad Dog" <[email protected]> wrote:

>:|Without researching too hard i can tell you that the front diff is a Dana 44
>:|and
>:|I'd swear up n down that's a Corporate 10 bolt n the back.

I agree on the Dana 44 on the front, but the rear DEFINATELY is an
Eaton w/ it's drop 3rd member and a round rear cover. Can't tell you
if it's a h052 or h072. I'd leave it though until you actually broke
it. those eatons had like a 12.5" ring gear on them, though the axles
were only 12 spline.

hth,
Bret