A test (archive)

If you can't read the diff letters and numbers, a test can be performed, but be VERY CAREFUL. If you jack the rear up and place the car on jack stands, you can put the car in neutral and rotate the rear wheels by hand. MAKE DAMN SURE THE CAR IS SECURE (chock the front wheels real tight and try to rock the car on the stands before getting under it). Once convinced it's secure simply rotate a rear wheel with the transmission in neutral and observe the other wheel. If it rotates the same as the one you're rotating, it's a LSD. If it moves opposite, it's an open diff. The ratio can be determined by placing a mark on the driveshaft, and carefully counting driveshaft revs vs. wheel revs.

Good luck, and again be real careful. If you are uncomfortable with this, or your car is badly rusted, take it to a garage with a lift, and perform these tests with the car up on a lift. Might cost a few bucks, but a decent garage will do it for free if they're not too busy.

: Don't say the obvious: that if I see pink elephants and the walls are moving then I am on LSD. There is some test that involves jacking up the rear of the car and spinning one wheel, but I don't understand the specifics. Can someone explain please. Is there any way to tell what the differential is, if it is there? (2.75, 3.25, whatever...)

: Muchas gracias.
: Jack Wasylyk

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