Brake fluid

coloradobluesky

coloradobluesky

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coloradobluesky
Is "Chevron Automatic Transmission Fluid Dexron III" ok for a Cleveland Brake Cylinder. Thanks in advance.
 
I would stick with MIL-PRF-5606
 
The seals in the brake system are spec'd for the 5606. They may not be compatible with any other fluid.
 
MIL-PRF-5606, MIL-PRF-83282 and MIL-PRF-87257 are all interchangeable and can be mixed.
 
Interesting. Though the OP's question had a pretty definitive answer, the questions it led to when reading up on the three different specs was fascinating.

I discovered 5606 is the SUCK. Flammable, low performance, ancient disaster.

Cleveland says go ahead and replace with 83282 everywhere (it's totally miscible with 5606). Is that actually legal on a certified aircraft? (Please tell me it is!)
 
arnoha said:
Interesting. Though the OP's question had a pretty definitive answer, the questions it led to when reading up on the three different specs was fascinating.

I discovered 5606 is the SUCK. Flammable, low performance, ancient disaster.

Cleveland says go ahead and replace with 83282 everywhere (it's totally miscible with 5606). Is that actually legal on a certified aircraft? (Please tell me it is!)
Click to expand...

5606 may be flammable but I'd rather use it than others that aren't. Lots of stuff in the airplane is flammable anyway...

Very generalized, a vendor such as Cleveland, Garmin, Whelen, Goodyear, didn't build the airplane. They may not even know exactly what aircraft their products are installed on so vendor service bulletins, letters, emails must be carefully evaluated as they can render an airplane unairworthy.

Cleveland didn't build the airplane or provide the flexible rubber brake hoses. Those buggers can run into the $1k of dollars to replace (such as Textron robbery style).
 
Just use 5606 and be done with it.
 
Everything is hydraulic on the Navion. I go through more 5606 than I do engine oil. A Navion owner wouldn't even notice the amount you're charging your Cessna brakes with.
 
Have a little fun. Put some aircraft hydraulic fluid in your car or motorcycle brakes. I made that mistake once.
 
Stewartb said:
Have a little fun. Put some aircraft hydraulic fluid in your car or motorcycle brakes. I made that mistake once.
Click to expand...

The flash point is only 95C! That would be a disaster!

bnt83 said:
5606 may be flammable but I'd rather use it than others that aren't. Lots of stuff in the airplane is flammable anyway...

Very generalized, a vendor such as Cleveland, Garmin, Whelen, Goodyear, didn't build the airplane. They may not even know exactly what aircraft their products are installed on so vendor service bulletins, letters, emails must be carefully evaluated as they can render an airplane unairworthy.

Cleveland didn't build the airplane or provide the flexible rubber brake hoses. Those buggers can run into the $1k of dollars to replace (such as Textron robbery style).
Click to expand...

Yeah, but 83282 is also required, by spec, to be compatible with seals and hoses. It's supposed to be a drop in replacement.
 
You'll never see the flash point. The master cylinder seals will melt into a glob long before that. Cha ching.
 
I think you deserve an honest and technically correct answer to your question. I don't have that answer; my bag is sparkies and such, but not chemistry. I would hope that somebody that is qualified to say WHY (and not just that a fluid that has been around since "befo de wah" is the *ONLY* correct one) would take the time to educate us ALL on why the fluid under discussion is not usable. I didn't say legal. I said usable. Has anybody thrown a brake hose or a brake o-ring into the stuff to see if it makes a balloon out of it? Or melts it into goo? THAT would be useful information. Speculation without proof ain't my strong suit.

Would I use it on the 182 without any of this information? HELL NO. But WITH the information it would then be my call as to whether the cost outweighs the liabilities. Would I sign off an airplane that I knew was doped with the stuff with or without the information? HELL NO. But then that's the owner's call, isn't it? And if it is being used on an experimental, that's what the word means, doesn't it? Remember, experimentals can be constructed from a cast iron bathtub powered by a flock of black swans if the builder can show by test or design that it will fly.

Jim
 
I'd be very careful about mixing or changing fluids. Do a lot of homework. As I recall 5606 is mineral based and hence the seals are designed for that. Some, like Skydrol on the other hand are ester based and will destroy many type seals. We found a problem when switching from one grease to another, both of the same mil spec, they hardened if the one was not flushed completely.
 
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5606 is NOT vegetable based, it's a petroleum base BY DEFINITION (I guess millions of years ago it may have started as vegetative matter). If it isn't petroleum, it's not 5606.

82382 is a synthetic hydrocarbon base equivalent to 5606 (equivalent mechanical properties). Still what you'd call oil.

There are phosphate-ester hydraulic fluids (Skydrol) but they are NOT compatible with 5606/82382 systems. Phosphate ester were usually a byproduct coal/coking operation in the past, but now are synthesized.
 
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What I do know is this.........In Alaska many amphibious float owners have switched from 5606 to Dextron, and have eliminated frequent cold operations problems.
 
I have no idea why. I've used typical aircraft hydraulic fluid in two sets of hydraulic skis for 15+ years down to -30ish temps and have never had any problems.
 
Just run down to Walley World and get some Mineral OIl. It's about the same as 5606 and is the spec fluid for BMW Motorcycles
 
So, after the "vegetable based" post earlier today, I figured I need to dust off the old books and see where I pulled that out of.... so, I did when I got back home just now. Page 291 of Aircraft Maintenance and Repair, Bent/Mckinley. "Vegetable-based fluids are usually mixtures containing castor oil and alcohol and are colored blue, blue-green, or almost clear. They are still used in some brake systems..." The next paragraph pertained to mineral based (red) fluids . And a third paragraph pertained to fire resistant fluids.
 
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