8 3/4 rear dimensions

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Dana67Dart

Dana67Dart

The parts you don't add don't cause you no trouble
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Just picked up a junk yard 8 3/4. It was in a bone pile so i dont know what it is out of and some of the measurements are not adding up from the varous sites that list such. The yard didnt have but 2 mopsrs in the 60 to 70s range, one was a 68 Belvidere and a 70s dustr with tubs neither had adiff in it.

Most things add up to 70 to 74 EBody but...

Breather is up on the hip of the housing not on the flat of the tube.

Large bolt pattern

Left hand threads on left axle

Oe axle bearings

Both axles look identical

Purches under housing

742 with Sure Grip / Power-Loc (editeded for the purest in the group), gears say 12 / 66 for date.

There was no tags on the diff, probably was apart at one time.

Small flange u joint

Druns have springs around the OD

One axle measures 30 inches on the end of spline to out side of wheel flange. 65 to 69 C body or 70 to 74 E body or 65 to 70 A100

One axle measures between 30 1/16 to 30 1/8 end of spline to outside of wheel flange checked and it doesnt seem to be bent. 65 to 66 imperial?

Housing measures 56 1/2 out side axle mounting flange to outside mounting flange. 70 to 74 E body?

Purch CL to purch CL 46.
65-'73 C BODY
70-'74 E BODY


Brakes are 11 x 2 1/2

What do you all think?
 
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It’s a pre 1970 housing, that’s for sure. They moved the vent tube down on the tube for the 70 model year. The center is also ore 69, as the 742 was discontinued in 69.
 
Dana67Dart said:
Just picked up a junk yard 8 3/4. It was in a bone pile so i dont know what it is out of and some of the measurements are not adding up from the varous sites that list such. The yard didnt have but 2 mopsrs in the 60 to 70s range, one was a 68 Belvidere and a 70s dustr with tubs neither had adiff in it.

Most things add up to 70 to 74 EBody but...

Breather is up on the hip of the housing not on the flat of the tube.

Large bolt pattern

Left hand threads on left axle

Oe axle bearings

Both axles look identical

Purches under housing

742 with trac-lock gears say 12 66 for date.

There was no tags on the diff, probably was apart at one time.

Small flange u joint

Druns have springs around the OD

One axle measures 30 inches on the end of spline to out side of wheel flange. 65 to 69 C body or 70 to 74 E body or 65 to 70 A100

One axle measures between 30 1/16 to 30 1/8 end of spline to outside of wheel flange checked and it doesnt seem to be bent. 65 to 66 imperial?

Housing measures 56 1/2 out side axle mounting flange to outside mounting flange. 70 to 74 E body?

Purch CL to purch CL 46.
65-'73 C BODY
70-'74 E BODY


Brakes are 11 x 2 1/2

What do you all think?
Click to expand...

Better watch what you say the (sure grip) cop is here! LOL
 
cosgig said:
They moved the vent tube down on the tube for the 70 model year.
Click to expand...

I thought it was around that time frame.


cosgig said:
The center is also before 69, as the 742 was discontinued in 69
Click to expand...

The gears seem to be December of 66.
I haven't cleaned it up yet so I only saw the date Im not sure what the ratio is yet but in is either 2.94( or the like) or 3.23 My buddy counted slightly greater then 3 turns to one wheel turn and I counted 3

Ill have to count the teeth
 
On a side note...

Best way to clean everything up?

My plan is to sell the axles, brakes and housing so I'll just pressure wash them and wipe dry maybe some wd 40 on the bearings. The center I'll use as is OR rebuild once the gunk is off. I was thinking of pressure washing the center then spraying it liberally with WD 40 or the like then bagging and store it in a sealed 5 gallon bucket it till i'm ready to use it. 6 months to a year.

Thoughts

pros --- cons
 
what threw me was the one axle being 1/8 longer, the vent location and gear date. a lot can happen in 45 to 51 years

(excessively fat fingers today!)
 
Dana67Dart said:
My mistake meant to say power-lock. It is a clutch type not cone type.
Click to expand...

In another post cosgig dogged people for calling it a posi, you got a sure grip by Chrysler's name but it is a Dana Spicer power lok in reality. Call it what you want but the cone style with the springs is a limited slip and not a true positive traction differential. You got it right but it's all funny, Call it what want and I don't think anyone really cares.
 
brian6pac said:
In another post cosgig dogged people for calling it a posi, you got a sure grip by Chrysler's name but it is a Dana Spicer power lok in reality. Call it what you want but the cone style with the springs is a limited slip and not a true positive traction differential. You got it right but it's all funny, Call it what want and I don't think anyone really cares.
Click to expand...

Well, my posi radar didn’t go off with that trac-lok comment. Gonna have to expand the dept, seems we have a lot of n’er do wells around this town!! Time to deputize Barn, Goober, and Judd, if he’s still alive that is.
 
72bluNblu & MoparLeo

Thank you. I looked at these locations before posting and a couple more I have, not listed above.

The housing seems to be 70-74 E body by overall width and purch CL, but the vent location is confusing says 69 and older? left over housing from 69 set to 70 dimensions?

Doesn't seem to have been modified but I haven't gotten the dirt off yet.
 
Catch me if you can
raw.gif
 
I knew I had a chart, see if this helps

Gone
 
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brian6pac said:
I guess I will delete that from my list
Click to expand...

There are a couple accurate measurements on it, but just a couple.

My favorite is always that it lists B body 8 3/4’s as being the same from ‘62-‘70. There’s 4 totally different dimensions for that year range, not to mention that before ‘64 they had tapered axles and ball and trunion yokes. No big deal right?
 
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