Originally Posted by Rusty

To keep the diff cool at the track. They have been known to run hot. When the stock VLSD gets hot. They don't work correctly. It's almost as an open diff. After a period of time. The stock VLSD just fails, and acts like an open diff all the time. That's why you see alot of the track rats changing the diff to something else. Like me. I changed to an OS Giken diff.