Differential Confusion

[Kryde]

I'm a little confused as to what type of rearend I have (who's going to make the first butt joke?). 

When I jacked one side of the car up I couldn't spin the tire.  With both sides up, the opposite tire spins in the same direction as the side I'm spinning.  I think the FSM says that's how the Sure-Grips work and that's what the previous owner said it had in it, so far everything was great.   

Now here's where I get confused, when I had the axles out I could see clear through the axle tubes.  A Sure-Grip is a clutch-type posi, right?  Shouldn't I see the clutch pack?  If that's the case, how do I figure out what I have?   

[Chryco Psycho]

Weird , both the cone & clutch have a cross pin preventing you from seeing through the diff , so you may have some type of aftermarket sure grip , do your axles have the green brgs on them or do they have adjusters , if they have adjusters you would have no way to set end play properly

[Kryde]

It has the green bearings on it now.  When I got it, it had the regular tapered ones but the adjusting collar (or maybe it was just the retaining tab missing, not entirely sure how it's supposed to look, but something's missing) wasn't there and the oil seal had been smashed to crap.

Is it possible I just have a spool?  If it is a spool how hard is it on the car to drive it on the street?

[Chryco Psycho]

spool makes the most sense
I wouldn`t try cornering hard with a spool; but it is OK on the street

[Mt.St.BigBlock]

Hi,
I think the Detroit Tru-Trac is a sure grip that is open thru the center. That would be awesome
is thats what is in there! Not crazy about the Green bearings. I understand Eaton sells a center
part now that allows both the Tru-Trac and tapered roller bearings to be used in the 8 3/4. Jeff