is this an open or locked diff

[rollingthunder]

Just bought this c7awe12 for my 9 inch for 70 bucks..the guy said it was a positrac with 3:50 ratio..is it an open or locked?? Thanks

 

[donsrods]

I think it is an open rear (non limited slip) but not sure. If you have a couple of axles slide them in and turn the yoke in it's normal direction. If the axles go the same direction it is limited slip, if they go opposite directions it is an open rear. If you don't have the axles watch the inside splines and you should be able to see them go the same way or opposite.


Don

 

[Torch]

hard to tell a detroit locker fits in a stock open 9" case. doesn't look like a limited slip. i cant see the bosses it should have where the clutch tabs would be on the inside.
The detroit locker for the ford 9" looks like the lock rite easy locker for the gm's that you put into a non posi case

 

[old lady's mad]

dose the whole carier look like that all round , the part in between the ring gears teeth and the carier brg. might be an early cast spool. they used to make some that looked like that before they started machining them nice and perty

 

[dannronn]

open or locked

Looks like a spool, no spideer gears.

 

[sgtpontiac]

Looks like a full spool.....

not big enough to have a posi unit or limited slip unit....so I guess you could call it a "posi"....as it will certainly will be spinning both wheels all the time!!

 

[440Clark]

If the ring and pinion are in nice shape you got a good deal, that case is very common but from what I've heard very strong. Bottom line do what Don said and spin the yoke. I seem to remember an article that stacked thrust washers in an open 9 inch turning it into a "poor man's posi".

 

[Rev Tex Devlle]

Looks like a spool, no spideer gears.

agreed~!

 

[ratrodz]

its open. the carriers on the trac locs has the ring gear bolts recessed into the carriers. the open carriers the ring gear bolts are flush.

 

[pistolpete]

Looks like a spool, no spideer gears.

I was thinking the same thing, no spiders. Looks a heck of a lot like the spool that I had in the rear of my offroad rig....

 

[rollingthunder]

Just as long as both tires spin I'm happy! .. I stuck the axle in and turned them...at first it spun in opposite directions but after two full turns it started to spin the same direction

 

[Torch]

the detroit locker for the ford 9" has no spider gears. there are clutches that the axles go into but they are not slip clutches like you think of as in a posi or in an automatic transmission.
They are pucks that look like castle tops. the teeth interlock with teeth in the case. there are several designs of detroit lockers some have big cases and some look like yours.
They way they work it the axle pucks are toothed into the case until one tries to turn against the other then it is unloaded from the case by a bendix or a wave cam or some mechanism allowing one axle to turn independantly from the case. It only unloads in the reverse direction so under power foreward causes both to lock in solid

heres some good info
http://www.kevinstang.com/Ninecase.htm
http://www.ringpinion.com/b2c//SpartanLocker.aspx

 

[Torch]

the only carriers that don't have spider gears are spools and lockers

 

[rollingthunder]

So basicaly I got a pretty good deal???

 

[blurooster]

check the passenger side gears , inside, if there are two sets it's a locker one set , open