Piper Flyer Association - Technical Know-how, Serious Fun read more

Topic-icon Brake Fluid

9 months 1 week ago #1916

It does appear to be an improvement over Mil-H-5606, which is the fluid that has been specced in light airplane brake and hydraulic systems since the beginning of time.
It looks like it's better due to non gumming qualities. I am not too worried about the increased temperature margins since I doubt there's ever any application in a Piper or Cessna that gets anywhere near 400 deg. F. The only caveat is problems at very low (-40 F) tempuratures.
The only hint that it's approved is from the Shell handbook, which I copied and pasted below. If you and your mechanic accept this as approval,then I would only use it after I had purged the old fluid out of your systems.
This is from the Shell Handbook on hydraulic fluids:
"All physical properties of MIL-H-83282 (now MIL-PRF-83282) were equivalent to or superior to those of MIL-H-5606 (now MIL-PRF-5606) except for low temperature viscosity. In particular all fire resistant properties of MIL-PRF-83282 are superior to those of MIL-PRF-5606"
I can foresee one problem. Even though the two fluids are supposed to be compatible, the old (5606) fluid is almost universal in maintenance shops, so if the fluid level ever needs topping and you don't have a container of the 83282 in the airplane and instructions to use it, 5606 may be added.

Happy Flying

Please Log in to join the conversation.

  • Jayson Slabach
  • Jayson Slabach's Avatar Topic Author
  • Offline
  • Subscriber
  • Subscriber
9 months 1 week ago #1915

Does anyone have experience using MIL-PRF-83282 in their piper? From what I can see it is supposed to be fully compatible as a replacement for and to be mixed with MIL-PRF-5606 but has lower flammability. My plan is to try it unless someone says it ruined all of their o-rings or some other unintended consequence. thanks,


Please Log in to join the conversation.

Time to create page: 0.160 seconds