Why is my car doing this? - 1

When i have the car 1994 ford taurus jacked up, if i spin a wheel clockwise the other wheel turns counterclockwise.

Added (1). Sorry i forgot to mention that is is the front wheels that do this. The car does not roll at all when it is on the ground.

Wevspyvd

It's an anti spin thing and been part of cars since the 1950's. That way if one of your wheels starts spinning the other will hold a grip.

That's telling you it's an Open Differential. If it was a Limited Slip or Locker it would turn the same direction

Do a search for "how do spider gears work in a differential" and that should explain it to you.

Yes… AND? What's your question?

This is caused by the differential gears. The differential allows the two wheels to both deliver power to the ground but also allows them to turn at different speeds when turning corners so that one of your tires doesn't get scrubbed (the outside tire path is longer so it needs to turn faster than the inside tire).

The differential is composed of a pinion gear that transmits power from the transmission to a ring gear on a carrier assembly. Inside the carrier is a set of spider gears that the axles are attached to. When driving straight the carrier rotates and the spider gears are locked which transmits power equally to both axles. When turning a corner, the spider gears are what allows one wheel to turn faster than the other by turning in opposite directions inside the carrier while the carrier rotates.

When both tires have traction in an open differential like yours, this works well, but when one wheel loses traction it spins and no power gets to the other wheel. When both wheels are off the ground and transmission is in park, the gear carrier is locked and only the spider gears can turn. Since they always turn in opposite directions it makes the tires turn in opposite directions when you turn one of them

Imagine that!

There are several gears connecting the left side to the right side, and the gears are driven by the transmission from the middle. This "differential" action allows the left and right wheel to turn at different speeds so you can turn around a corner, while delivering engine power to both tires (to move the car). Otherwise, one or both wheels would skid or something mechanical would break, if the traction was too great to skid.

In operation, the car is not driven from one side while the other side is disconnected from the ground (as you are doing).

The differential consists of a side gear connected to each axle, and 2 or 4 spider gears connecting the side gears to each other, with all of these gears inside the ring gear carrier. You need to see one for it to make sense.

-General automotive mechanic since 1972. Retired in 2018.

That is the diff, causing it, that is perfectly normal

It's the planetary gears inside the differential. Hard to explain without a cutaway of a differential so you can actually SEE what's happening.