Ok my car is on jack stands right now and I decided to wash it. A day after, I realized that the rotors are rusted so what I did was turn on my car (my car still on jack stands) and just run my car until the rust go away... So I put it on first gear and let the rotors spin (I took off the wheels) and I realized that the Rear Right rotors is not spinning but the rear are just fine.. Is this because my car is not on the ground? I just changed my transmissions/TC/Rear Diff. fluid too.. I hope nothing is wrong with my car.. can anybody say some words for this?

 

Unless you have a rear locking differential, what you are describing is completely normal

 

just put ur wheels back on and go drive ur car...use ur brakes...this will remove the rust off ur rotors

 

Hold the left side and the right side will spin....






Seriously, don't do this you'll hurt yourself.

 

i have a similar question...i was changing my summer rims/tires for my winter ones the other day and when the front was jacked up the wheels would spin by hand while the car was in gear and rears were on the ground. i never remember it doing that before. The backs did the same thing while in gear and the fronts on the ground, i would think if the car is in gear and you turn a tire you should also be turning over the engine right? Or at least the rest of the AWD system?

 

+1

 

Nope. Your only turning one wheel. Try and turn all 4 at once in the same direction, then its not going to turn. You have differentials, so even though its an AWD system its not LOCKED in AWD. Your not even locked in 4wd. The differential allows the wheels to spin at different speeds (ie: turning a corner). If you have ever jacked up a 2wd vehicle and left it in gear and tried turning one wheel you would notice the other wheel turns the opposite direction with an open differential. A limited slip differential does not lock the wheels together to the same speed.

If you really want to understand what is going on:

http://auto.howstuffworks.com/differential.htm

 

ok nomore worries for me...

 

http://www.howstuffworks.com = FTW!!!

 

Haha, I love this answer...

And, I dont know if I'd trust turning on the car and putting in gear spinning wheels while on jack stands....please be careful