Gear Oil smell
 

Hey guy's, is it normal to smell gear oil inside the cab after running the car hard?

No,unless you have just set a land speed record there shouldn't be any oil smells inside the car.Engine oil can leak out onto hot manifolds while running at high RPM's.Are you sure it's gear oil?

it's probally that rotten egg smell. It comes from the cats.

Or the clutch being worn..

Did you just change out your rear-end gears?