I have converted several vehicles to DOT 5 when I completely redid the brake system. I have been happy with it, going over 10 years with no issues, The key is the system has to be cleaned of all DOT 3 or 4 (or 5.1) fluid. Just draining the system and refilling with DOT 5 will cause compatibility problems. I have not had to do any major brake work on my Plus 8, so I am still using DOT 4 and changing the fluid every two to three years. When I have to rebuild the brakes I will switch to DOT 5.
