[Stan-in-Spokane]

A friend of mine was telling me that with an open differential, if one tire has traction and the other has none, that the tire with none will spin twice as fast as the speedometer reads. I said no way, his son got on the Internet and found a crawler website, that stated, for instance, a vehicle in icy conditions with one tire on pavement, and the other on ice, could try to accelerate, the speedometer could read 60 mph, but the tire with no traction, being the one on ice could actually spin at a rate equal to 120 mph. Could some one please explain if this is correct, and how this gear multiplication works? Because if this is true, I just don't get it, Thanks for any response. Stan....

 

[Mike]

Yeah ,it's true.
It's caused by the gear multiplication of the spider gears and the pinion gears -similar to how an auto trans changes gears by stopping the drum.

 

[bigblockwagon]

Yeah ,it's true.
It's caused by the gear multiplication of the spider gears and the pinion gears -similar to how an auto trans changes gears by stopping the drum.

It's true until you launch spider gears thru the back cover, then neither wheel turns One wheel burnouts are really tough on the diff, I learned this firsthand as a 16 year old kid years ago.

Scott

 

[big gear head]

Yea, it is true. You end up with a cross shaft that looks someting like this,

and a case that looks like this.

 

[Mike]

see if this helps explain it:
http://auto.howstuffworks.com/differential2.htm

I knew I saw this somewhere.

 

[Stan-in-Spokane]

Thanks for all the replies, I will have to apologize to my friend, because I called bull@#$t. All of my cars were open differentials when I was a kid, and would only burn one tire, I see the concept, not sure how they apply the same torque to both tires, yet let one spin like crazy, while the other one sits still. I will talk to my local gear shop, a guy I have done business with, maybe he can get it through my thick head, thanks again..