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Old 05-04-2005, 04:54 AM   #26
4x4Poet
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Quote:
Originally Posted by 72MARIO
Oky, So am I stil good to go with the silicone ? Just change it every 2 years ?
Looks like a big yes all around, 72MARIO.
Quote:
Originally Posted by tom hand
The only problem you will have with it if changed over properly, is that is doesn't work well at high altitudes...somthing to do with the boiling point. If you go to really high altitude you will have a spongy pedal and there is nothing you can do about it...at sea level you will have no problems and it will save the paint
I've heard of the spongy pedal problem. Never knew why until now.
Quote:
Originally Posted by mr402
I haven't heard too much about the synthetic brake fluid. Is it any better as far as not eating paint? 4X4 what was your experience with it?...
Synthetic brake fluid definitely eats paint. No need to ask me how I know. I found it last Fall just as I was overhauling my TravelAll's brake system. New master; SS braided hoses; PDB shoes, springs, and wheel cyls; a few new SS hard lines mixed in with the old. The brakes work great, but I haven't noticed anything superior about it. I just figured that, like synthetic oil, it would not break down as easy and maybe not absorb as much moisture as petro brake fluid.
Quote:
Originally Posted by neonlarry
...Brake fluid should be changed about as often as antifreeze, every year.
Great point, neonlarry. I think I have a good flush tip. I don't have a mityvac, so I use one of those battery bulb suckers (tech name) to suck out most of the fluid from each reservoir without letting air hit the bottoms so as to keep air out of the system. (I use a coffee can to catch the fluid with rags under the master.) Then, I fill each reservoir with new and, while keeping the reservoirs full, bleed the brakes till I see new fluid come out. This way I don't flush all the moisture ridden reservoir fluid thru the lines and past the calipers/wheel cyls. And fresh fluid hits the bleeders sooner.
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Last edited by 4x4Poet; 05-04-2005 at 05:01 AM.
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Old 05-04-2005, 06:37 AM   #27
Big69C20 Toy
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Okay fellas, main reason for OEMs typically not using higher grade fluid is cost and the fact that most vehicles DO NOT require any sort of higher end fluid.

As stated Dot 3&4 are hydroscopic and absorb moisture (depends on how good the seals are all over) very slowly.

Moisture in the brake lines does significantly lower boiling point on vehicles but as stated those conditions are typically not apparent for an average hot rodder or even most road racers. The BIG problem for vehicles is substantial sustained braking. If you've got your truck loaded up to the gills at or over GVWR and you decide to go down a MONSTER (ie from Towne's Pass to Stovepipe wells in Death Valley, CA) hill you have quite the ability to heat up those brakes and the fluid... If you get it hot enough you boil the fluid in the caliper and you're in BIG trouble

That being said the rate of absorbtion of moisture in systems is usually VERY slow (i'm totally unsure on these old trucks of ours). As far as how well our trucks perform under 'extreme' braking, your guess is as good as mine, many tests and procedures now in place with the auto industries did not exist back when these trucks were created.

Back to the original ?... running silicone fluid into a completely dry system. This should be perfectly fine IF (and you have no way of knowing exactly unless you contact them and can drudge out an anser) the seal manufacturers tested their parts to be able to withstand silicone fluid. If the seals cannot handle the fluid it will degrade them, causing leaks and possible failure over time.

If it were me i'd say go for it and odds are VERY good that it'll all be fine and dandy, just do system bleeds every year or so for top performance to help keep moisture out.

Hope you guys take my words as opinion/advice but i do know HARSH testing procedures for brakes and many of the standards the industry has to live by and with you guys can guess why
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