Need to upgrade the diff

[Foghorn leghorn]

Hi everyone, I have the opportunity to purchase an A body posi diff with 3:55 gearing. The diff has been apart for several years and there is some surface rust on the crown gear. He was planning to rebuild it, but never did. Included are the axle bearings and clutch pack. He is being vague about the price and asked me to make an offer. What would be a fair price for an unknown posi diff that's apart? He said it's the smaller 741 Case (whatever that means) My 71 Duster had a 360 installed but was a slant 6 .

 

[ch1ll]

$200

 

[Desoto291hemi]

Is this the complete read end or just a chunk ?

Tommy

 

[CFD244]

Let's see some pics......

 

[AJ/FormS]

I sold one with a 4.30 in it, for $450C a few years ago, assembled, and broke-in. I couldn't see me ever running a 4.30 again. The guy was a friend, and I needed the cash.

 

[RustyRatRod]

I agree about a low offer. That will do one of two things. Either score you a deal or he'll throw out another number.

 

[413]

Do you really want to buy a basket case rear with rusted ring gear?

Is it a cone or a clutch sure grip?

A cone I wouldn't take it if it was free.

 

[ch1ll]

If I was going to cough up major cabbage for a rear axle, none of this used, disassembled, rusted, needs rebuilding ****. You won't know what you got until you got it rebuilt, in the car and your rolling down the road. On top of that, it's the weaker of the 8 3/4 axles and even the 742 isn't known for the higher performance strength. Every time I buy used good deal, it ends up more money in the long run. For my money I'm buying a 3rd party reman from a reputable builder with a warranty.

 

[A56]

Pay extra and get one that's complete ready to go from someone reputable-2 cents

 

[junkyardhero]

i sold a 3.91 SG 741 a few months ago for $550 and it was perfect in every way.

i'd be offering yard prices if it were together, and less than that if it were in pieces. 2~250 max

 

[Foghorn leghorn]

Is this the complete read end or just a chunk ?

Tommy

It's complete, but completely disassembled and has surface rust visible on the crown gear. Waiting for pics from the guy.

 

[YY1]

Is this an 8 1/4?

 

[Foghorn leghorn]

i sold a 3.91 SG 741 a few months ago for $550 and it was perfect in every way.

i'd be offering yard prices if it were together, and less than that if it were in pieces. 2~250 max

Thanks! I am waiting for pics he says he's going to send.

 

[Foghorn leghorn]

Is this an 8 1/4?

Sorry, my mistake It's an 8 3/4.

 

[YY1]

Yes it is.

I thought it might be.

Lots of replies have been related to the 8 3/4.

 

[Desoto291hemi]

In the 1st post it was implied that it was an 8 3/4
He mentioned a 741 case number

Tommy

 

[RustyRatRod]

Yes it is.

A rusted disassembled 8 1/4? Tell him 100 bucks.

 

[33IMP]

741 would be a small pinion 8 3/4.
8 3/4 housing and axles for an A-body are worth what some here are saying for the complete rear.
Imo, an 8 1/4 (tho perfectly adequate for a mild 360) is worth about a quarter of an 8 3/4, and I wouldn't bother with a rusty-8nside one.
And again imo, if it's an 8 3/4 clutch suregrip (for goodness sakes, NEVER a "posi"!), that alone is probably worth $200.

 

[33IMP]

A rusted disassembled 8 1/4? Tell him 100 bucks.

...and thats generous.

 

[Foghorn leghorn]

A rusted disassembled 8 1/4? Tell him 100 bucks.

Sorry, I meant it's an 8 3/4

 

[RustyRatRod]

Sorry, I meant it's an 8 3/4

Same answer.

 

[Foghorn leghorn]

It is slim pickens where I live, (Saskatchewan)so I want to go check it out in person. then I will decide. Thanks for giving me the background on these. Never dealt with a diff swap before.

 

[Captainkirk]

I'm also on board with the 2-250 offer based on condition. Unless it is in good condition, which it's obviously not.

 

[340six]

741 would be a small pinion 8 3/4.
8 3/4 housing and axles for an A-body are worth what some here are saying for the complete rear.
Imo, an 8 1/4 (tho perfectly adequate for a mild 360) is worth about a quarter of an 8 3/4, and I wouldn't bother with a rusty-8nside one.
And again imo, if it's an 8 3/4 clutch suregrip (for goodness sakes, NEVER a "posi"!), that alone is probably worth $200.

I agree. Never Posi.
The Dana Power-Lok units utilized clutches

1969-1974 (489) used the Borg Warner Spin Resistant (commly called Cone)

 

[Foghorn leghorn]

I made my offer and waiting to hear back. He's really slow to reply! this is what's in my car now. Can't find any numbers, but came with the slant 6 and isn't a suregrip. Massive play in the crown and pinion as it now has a semi built 360 that the previous owner was likely hard on.