[Roadsters] Smoker?

[Graeme]

They are referring to AUTO trans. Fluid.
By design it is laced with detergents to keep the insides of the Auto
extremely clean.
The problem is that an Auto. has myriads of tiny passages and holes to make
the think work so they must be meticulousy clean. 
I guess the theory and practice is that these same detergents loosen and
remove interior crud on the engine as well.
 
"Is that automatic transmission fluid or manual transmission fluid or
exactly what kind of tranny fluid?

Linda"