Can you I.D This Rear end

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memike

memike

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I myself and a friend removes this rear end out of a 68 or 69 383 cuda 7 years ago in a scrap yard.

But can the numbers on the rear end give the year and or gear in it.

A tec's test for sure:cheers:

Good luck,

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vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv 076.jpg
 
8.75,but if there is no tag on one of the bolts,i cant tell you from here what gear is in it.Could be from 2.76-3.91 in that case.Is it a sure grip?
 
The part number looks to be 2070742, which makes it a 742 8.75 rear. This same number was used from 59 - 68. As for the ratio, you will need to look for a tag attached under one of the bolts attaching it to the axle housing. If you don't see one, then remove it from the axle housing and the gears will be stamped with the ratio, or should be. To find out what the axle housing is, just messure it and then post the results, someone should be able to ID it by the width. You can also meassure center to center on the spring perches. A-bodies are 43 inches if I remember correctly.

The 742, was supposed to only be on B, C and D bodies, so if this is a A body axle housing, the pumpkin may have been swapped.

My Barracuda was a 7.25 rear from the factory. But I put a 8.75 on it, and then a 742 3.23 suregrip. So that proves that things can happen over 40 years.

valentek
69 B5 408 FB
 
The numbers are 2070742 then
the number 18 and then you can see the big #2
spring perch is 43" apart and the back plate's from the in side is 51"
I have not opened it up yet to find what gears ar in side.
I am hopping on finding a sure grip with 3.23 or 3.55.
This will be a long revamp , new studs and hubs,brakes and allot of elbow grease, But I am looking forward to getting this rear end looking and working buy spring.
Thanks for the help that I will figure may be hard to figure out, if at all.
 
Mike you can tell what gears you have just by spinning the yoke and counting how many turns it takes to make the drums to make one complete revolution. In other words if you have to turn the yoke 3-1/2 times it's a 3.55 gear. 3-1/4 times would be a 3.23 gear. You can also tell if it's a sure-grip by having a buddy turn one drum and you try holding the other. If their locked together it's a sure-grip. If one turns one way from the other it's an open.

Check to see if it's an open or sure-grip before you do the gear count cause if it's an open rear you have to have 2 guys turn the drums exactly equally one turn and count the turns of the yoke to get the ratio. Kinda opposite of how you do it with a sure-grip.

BTW: if it is a sure-grip chances are real good it's the good Dana powerlock cause that's all that came in the 742 case. Hopefully nobody has changed it.
 
fishy68 said:
Mike you can tell what gears you have just by spinning the yoke and counting how many turns it takes to make the drums to make one complete revolution. In other words if you have to turn the yoke 3-1/2 times it's a 3.55 gear. 3-1/4 times would be a 3.23 gear. You can also tell if it's a sure-grip by having a buddy turn one drum and you try holding the other. If their locked together it's a sure-grip. If one turns one way from the other it's an open.

Check to see if it's an open or sure-grip before you do the gear count cause if it's an open rear you have to have 2 guys turn the drums exactly equally one turn and count the turns of the yoke to get the ratio. Kinda opposite of how you do it with a sure-grip.

BTW: if it is a sure-grip chances are real good it's the good Dana powerlock cause that's all that came in the 742 case. Hopefully nobody has changed it.
Click to expand...

Thank you for your wisdom fishy68,
and everyone that has posted here.:cheers: my eyes are open now.:-D
 
fishy68, you are one knowledgeable being! I've seen quite a few of your posts and you never cease to impress me, and on top of it, the things you say make sense. Good on ya!
 
fishy68 said:
Mike you can tell what gears you have just by spinning the yoke and counting how many turns it takes to make the drums to make one complete revolution. In other words if you have to turn the yoke 3-1/2 times it's a 3.55 gear. 3-1/4 times would be a 3.23 gear. You can also tell if it's a sure-grip by having a buddy turn one drum and you try holding the other. If their locked together it's a sure-grip. If one turns one way from the other it's an open.

Check to see if it's an open or sure-grip before you do the gear count cause if it's an open rear you have to have 2 guys turn the drums exactly equally one turn and count the turns of the yoke to get the ratio. Kinda opposite of how you do it with a sure-grip.

BTW: if it is a sure-grip chances are real good it's the good Dana powerlock cause that's all that came in the 742 case. Hopefully nobody has changed it.
Click to expand...

Thanks for posting this, someone told me once about the counting the turns of the yoke trick, then somebody said thats not acurate, what your describing makes sense. Now I know what I'll be doing next time I get the back of my car on stands! Already know its a suregrip rear in my car, don't ask me how I know this:burnout:
 
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