[Thedeputy]

Is there a way to tell if the rear axle is equipped with a spool or a limited slip without taking out the carrier? The reason I'm asking this, is a because a friend of mine bought a 1965 coronet 2dr sedan and you can really here the tires chirp when he's going around a sharp corner. The seller told him there is a posi inside, but hearing the grinding of the tires on the road I suspect a spool.

Thanks, Antoon

[dave-r]

If the rear tyres are REALLY wide (M/T Sportsmans etc) they will scrub and chirp even with just a limited slip diff.

If this is not the case it would be hard to tell I guess. Try jacking up only one wheel and see if you can turn it either way at all.

[Jon]

Another angle is to jack up the rearend and turn one tire, the other will spin opposite on a spool differential. Both will go the same way with a good "posi". Listen for any strange noise at the same time.

Any grinding or clicking could be the spider gears or a pin going bad.

[fbernard]

Another angle is to jack up the rearend and turn one tire, the other will spin opposite on a spool differential.

Wheels wil turn in opposite directions only with an open diff (or a Torsen when it's not loaded).
Spools will make the wheels turn like a LSD, in the same direction.
The two axles are totally tied together with a spool.

you can try to lift only one wheel, leaving the other on the ground, with parking brake set and a block of wood in front of a front wheel (transmission in neutral).
Try to turn the lifted one by hand (really try) in forward motion. A LSD will let you turn (won't be easy if it's new, you may not even be able to turn it). With a spool, you won't turn the wheel at all. If it's too easy, the LSD is shot and needs to be changed or rebuilt (but it won't be the case if your tires chirp).

You can try pushing the car with the front wheels turned.
I had to help a friend push his at a drag strip a couple years ago, it takes a few strong guys (or even more weaklings like me) to move a car with a spool. But again, it may be the same with a really tight LSD.

Or you can try to look with a lamp through the oil plug hole on the venter section, you may be able to see part of the diff/spool.

It's not very hard to pull it out for a check, though, if you have access to a lift.

[Jon]

Sorry, thought spool meant open differential. Once created a spool from an open diff by accident. It didn't last to long though.

[Thedeputy]

The tires are pretty wide indeed. We'll try jacking it up on one side and see what happens.

Thanks,

Antoon