anybody ID this 8 3/4 ?

[hdwrench]

i’m not entirely familiar with these? any opinions on the ratio , numbers stamped not telling

 

[cr8crshr]

489 case...Cannot see the gear ratio on the ring gear as it should be stamped somewhere on it. 489 case isn't as popular as the 742 case and the 491 case isn't as popular also. Also appears to have a sure grip along with the ring and pinion...cr8crshr/Bill

 

[RemCharger]

Looks like a decent ratio, but the gears look like junk so it's irrelevant.

 

[1 Wild R/T]

489, cone style S/G, by the width of the ring gear I'm gonna guess 3.91 or 4.10.... The pinion nut got loose and the pinion gear slid back and attempted to eat the carrier...

After a second look might even be 4:30 or 4:56

 

[dadsbee]

Roll it..the gear ratio is ON the ring gear. That grease or rust? I think I know the answer...

 

[1 Wild R/T]

Looks like a decent ratio, but the gears look like junk so it's irrelevant.

They are definitely crusty... And I'm betting the pinion teeth are chewy... But if you were just putting together a beater hotrod I'd clean them up and use them... Know they'll be noisy... Who cares? If ya want better, buy better...

 

[hdwrench]

asking price is $500 , if it got loose and ate itself it’s probably not worth much ! it’s couple hours from home so not easy to view … 3.91 or 4:10 interesting but ….and the crust on gears looks like some grease but not enough or is it hiding something?

 

[1 Wild R/T]

That's the $100 junk pig for a beater.... IMO $500 for that is a pipe dream....

 

[Runcharger]

Yup: Not anywhere near a $500 piece. Not worth the trip. Probably 4.30 or 4.56 by the width of the ring gear. Crappy limited slip that's most likely worn out.

 

[dadsbee]

I bought this PERFECTLY good 3:23 x 742 for $600 Canuck bucks last year to build the rear end for the '64. Yes I know I got lucky....

 

[hdwrench]

I bought this PERFECTLY good 3:23 x 742 for $600 Canuck bucks last year to build the rear end for the '64. Yes I know I got lucky....
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looks new inside !!! nice deal …

 

[hdwrench]

thanks for the help guys , i’ll keep looking…

 

[Richard Cranium]

I bought this PERFECTLY good 3:23 x 742 for $600 Canuck bucks last year to build the rear end for the '64. Yes I know I got lucky....
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Show off!

 

[1STMP]

You could count the number
ring gear teeth and devide
that by the number of pinion
teeth, to get a ball park on the ratio.
Agree with others here. That
set-up as it exists, is not
worth $500.
Check out Drivetrain
America. From what I
remember, you can rebuild
that diff for less than $500
with whatever gears you
choose, given the case is in
good shape.
8-3/4 diffs are getting harder
to find at decent prices. And
most of what you do find
needs to be rebuilt anyway.

 

[33 IMP]

The scars on the cone sure grip mean to me that the pinion bearings are junk, the cone suregrip probably needs work, and it's a bunch of chewed-up gear.
M.O.? Worn out race piece. I'd give $200 tops. (For the case and suregrip only, the rest is junk).

 

[33 IMP]

I bought this PERFECTLY good 3:23 x 742 for $600 Canuck bucks last year to build the rear end for the '64. Yes I know I got lucky....
View attachment 1608730View attachment 1608731View attachment 1608732View attachment 1608733
View attachment 1608734

Cone suregrip in a 742?

 

[1STMP]

The scars on the cone sure grip mean to me that the pinion bearings are junk, the cone suregrip probably needs work, and it's a bunch of chewed-up gear.
M.O.? Worn out race piece. I'd give $200 tops. (For the case and suregrip only, the rest is junk).

Agree with your assessment.
Of course counting the
sure grip as usable.
A bearing kit is about $190,
with a ring and pinion being
around $250.

 

[hdwrench]

$500+$190+$250 +$labor / makes the new chunk from dr diff w choice of ratio look reasonable at $1320 ….

 

[1STMP]

$500+$190+$250 +$labor / makes the new chunk from dr diff w choice of ratio look reasonable at $1320 ….

Initial cost for that piece of
junk wouldn't be anywhere
near $500. All the OP would
be paying for is the case and
a questionable locker. $100
at most. Let's give the guy
some credit as to his
wheelin' and dealin'
capabilities.
It is rebuildable, and
probably at a cost most
can afford.
I rebuilt mine for less than
$500...

 

[1 Wild R/T]

Cone suregrip in a 742?

Look again, that is a clutch S/G, ramps and wedges....