Open And Limited Slip

Straight6 · Oct 2, 2004

If two 9" third members, one a true trac and the other an open diff were sitting next to each other on a bench how would I tell the difference between the two?

Seabronc · Oct 3, 2004

Here is a picture of a trutrac.

Straight6 · Oct 3, 2004

Attached you will find a picture of what I purchased off of ebay, I do not know enough about diffs to indentify this so what is this?

Seabronc · Oct 3, 2004

OK, I can't see the other side of the ring gear, but from this side it appears to be a standard stock oper differential. Was there a tag on it? A traction lock limited slip differential will have a a L in place of the decimal point between the ratio numbers.

ex. bottom of tag should look something like ( 3.50 9 108 A ) for standard open diff. or (3L50 9 108 A) for a limited slip diff. Indicating 3.50 gear ratio with a 9 inch Ring gear diameter.

God luck,

>-

Seabronc · Oct 3, 2004

PS, if you don't have a tag to go by, the Trction lock Limited Slif Differential has a "S" shaped preload spring on the other side in the center between the gears with the top and bottom of the "S" facing the axle gears. The clutches are behind the axle gears.

Good luck,

>-

STLKIKN · Oct 4, 2004

Sorry seabronc, you can't visually identify a 9" in quite the same way as an 8.8 or a Dana....
Flip the centre sections so you can look into the side gears for the left axle, the pinion yoke will be at the bottom of the centre touching your work bench.
Make sure you have enough light to see into the carrier through the adjuster.
An open carrier will have one side gear on the left side, a "posi" will have a two piece side gear that looks like there are two gears on the one side.
I hope that make sense, and that it helps....
Also, make sure that the side gears fit your axles (31 spline), kind of a bugger to find out you have the wrong side gears AFTER putting the centre in!!( older 9" diffs are 28 spline.)