Disclaimer: I am not an engineer nor is the following review based upon a double blind placebo test. However I am a good wrench and explorer willing to share my experiences whether right or wrong. After my curiosity got the best of me, I decided to use Mobil 1 synthetic transmission fluid in the outer chamber of my forks and I used maxima 5wt in the inner chamber. I came to the conclusion that the two chambers would not mix. Well apparently they do share or mix somehow. The Maxima is very translucent light blue oil and as you all know the trans fluid is red. After about 20 hours I decided to change the fluid. Guess what color the inner chamber was……..Yep, it was red. Yah weird? How did the forks perform? You ask? They were amazing but I need to throw in a wrench. Upon inspection of my fork bushings they didn’t have wear but had a weird bumpy puffiness about them, almost like a chemical reaction with the Teflon. I cleaned the bushings and let them set, the puffiness settled down and the bushings looked normal after 24 hours (I replaced the bushings anyway for those wondering). My conclusion: the trans fluid isn’t compatible with the Teflon coating on the bushings and there is a sharing of oil between the outer and inner chambers. That being said, the forks worked very well despite my findings.