Have a friend that has a 1500 Wing and needs to add brake fluid . Its calls for Dot 4. all we found is Synthic Dot 4 . Will this mix with the fluid in the brake system without causing any problems.
I do the same thing. I just feel better about the flush if I know I have completely flushed the system and I have nothing but new clean fluid in the lines. When the MityVac container has very clean fluid in it, I know the job is done.Nonetheless, I always flush out all of the existing fluid 2 or 3 times before putting in new. By flushing I mean fill each reservoir and then flush that fluid through 2 or 3 times.
This stuff has replaced Valvoline's Syn-Power. Actually, it's likely the same stuff with a new label. Fully compatible with any regular DOT 3 or 4 brake fluid. Don't confuse the word "synthetic" with silicone-based stuff like DOT 5. Synthetic doesn't necessarily mean silicone.The last container of Valvoline synthetic brake fluid I bought clearly said compatible with either Dot 3 or Dot 4 brake fluids. I wanted the compatibility for replacing or flushing existing Dot 3 fluid, but it should apply to adding also.