Joined: Aug 2010
Location: Independent Hill
774 Miles since added XL-18. I have found it has lost some of it's effectiveness. One of the biggest changes I noticed that finding first from a stop was much easier and never had to reset. That has degraded some. Cold shifting unfortunately is still a problem and I continue to skip 2nd until engine is at operating temp. Is there an overall improvement in feel? Yes. It did improve things so the additive certainly did not hurt.
2011 Sterling Grey GT Premium, 6MT, Brembo, 3:73, GT500 axlebacks, tint, Rousch white billiard ball shift knob, Stack Racing lower black billet grille.