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| | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 | Went into my local O’Reilys to purchase a qt of brake fluid. The entire selection was synthetic! What are you guys using in your older vehicles? I was able to get non-synthetic 2 years ago to do my ‘62 C-10.
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: Dec 2001 Posts: 14,522 Moderator: Welcome Centre, Southern Bolters, Legion Hall | | Moderator: Welcome Centre, Southern Bolters, Legion Hall Joined: Dec 2001 Posts: 14,522 | Been using the DOT 4 for some time. Never a problem. Its still stocked on the shelves around here. | | | | | Joined: Aug 2018 Posts: 1,004 'Bolter | | 'Bolter Joined: Aug 2018 Posts: 1,004 | i'm not sure what is meant by "synthetic" vs non with regards to brake fluid
however when it comes to substituting with modern products this is the rule
Dot 3, 4 or 5.1 brake fluid are all compatible and can be mixed to any ratio.
You will simply end up with a mix that is part way between the specifications of the two fluids.
example 1, vehicle states to use DOT 3, use any of the above, or a mix.
example 2, vehicle states to use DOT 4, use DOT 4 or DOT 5.1 or any mix thereof.
DOT 5 is silicone based, it CANNOT be mixed with the above, must use only DOT 5 for replacement fluid.
example 3, vehicle states to use DOT 5, only silicone type maybe used
| | | | | Joined: Jan 2003 Posts: 354 'Bolter | | 'Bolter Joined: Jan 2003 Posts: 354 | I worked in a plant that made brake fluid in the mid 70's. All brake fluid on the market at that time was synthetic, some was labeled synthetic some was not. My preference is DOT 4 fluids that are labeled "low moisture activity" or something similar. Those have an additive that essentially neutralizes small amounts of moisture.
Harold Wilson
41 Chevy 3/4 Ton
| | | | | Joined: Jan 2002 Posts: 2,839 'Bolter | | 'Bolter Joined: Jan 2002 Posts: 2,839 | I had to go out to my shop to see what I use. Valvoline synthetic 3,4
Craig My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
| | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 |
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: Dec 2002 Posts: 3,441 Moderator - The Electrical Bay | | Moderator - The Electrical Bay Joined: Dec 2002 Posts: 3,441 | Interesting subject. I was looking for some brake fluid to put into my vehicles and I hope it was not DOT 5!
Another quality post.
Real Trucks Rattle
HELP! The Paranoids are after me!
| | | | | Joined: Sep 2013 Posts: 1,362 'Bolter | | 'Bolter Joined: Sep 2013 Posts: 1,362 | Rusty, all the dot5 I've seen is purple to help avoid mistakenly adding it to anything else.
RonR
1951 3600 with Clark flatbed, T5, 4.10 rear
1970 340 Duster
1990 5.0 V8 Miata (1990 Mustang Gt Drivetrain)
1964 CJ5
| | | | | Joined: Jan 2017 Posts: 23 'Bolter | | 'Bolter Joined: Jan 2017 Posts: 23 | Been using the DOT 4 for some time. Never a problem. Its still stocked on the shelves around here. Been using DOT 4 forever too. Was sold on the fact that it has a higher boiling point and just better than lower numbered DOTs ; )
1954 3600
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