The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Suspension

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 05-03-2019, 10:48 AM   #1
69SCSS
Registered User
 
69SCSS's Avatar
 
Join Date: Aug 2012
Location: Neskowin OR
Posts: 1,153
Brake line fitting size

My front disc line going from the prop valve to the T at the frame rail has a crack, and looking to replace it (it's leaking a drip of brake fluid each time I drive). What is the fitting size, 7/16-24? I found a couple replacement brake lines but since I need to keep the line on until I replace it (had to drive without it), I can't really bring it down LOL

My flare kit sucks and I need to replace it, otherwise I'd just fix it... but the line is really old and tweaked, so prob a good idea to replace it completely anyway.
Any help is appreciated.
__________________
My 68 SWB
Al Silveira Music
<- My daughter loves this guy 8-)
69SCSS is offline   Reply With Quote
Old 05-03-2019, 12:10 PM   #2
The Rocknrod
Moderator

 
The Rocknrod's Avatar
 
Join Date: Aug 2011
Location: China Spring, TX
Posts: 7,280
Re: Brake line fitting size

Just FYI:
3/16" brake line flare nuts are 3/8"-24 - https://store.fedhillusa.com/316475m...elinenuts.aspx
5/16" lines are 1/2"-20 - https://store.fedhillusa.com/5168mmf...clinenuts.aspx
3/8" lines are 5/8"-18 - https://store.fedhillusa.com/38directory.aspx
Hope that helps.
The Rocknrod is offline   Reply With Quote
Old 05-03-2019, 12:15 PM   #3
69SCSS
Registered User
 
69SCSS's Avatar
 
Join Date: Aug 2012
Location: Neskowin OR
Posts: 1,153
Re: Brake line fitting size

Quote:
Originally Posted by The Rocknrod View Post
Just FYI:
3/16" brake line flare nuts are 3/8"-24 - https://store.fedhillusa.com/316475m...elinenuts.aspx
5/16" lines are 1/2"-20 - https://store.fedhillusa.com/5168mmf...clinenuts.aspx
3/8" lines are 5/8"-18 - https://store.fedhillusa.com/38directory.aspx
Hope that helps.
Cool thanks for the reply. So that line is 3/16" then, and the nut is a 3/8", so that's probably the correct one then?
https://www.summitracing.com/parts/a...8303/overview/
__________________
My 68 SWB
Al Silveira Music
<- My daughter loves this guy 8-)
69SCSS is offline   Reply With Quote
Old 05-03-2019, 01:02 PM   #4
mongocanfly
Post Whore

 
mongocanfly's Avatar
 
Join Date: May 2015
Location: Alabama
Posts: 14,557
Re: Brake line fitting size

just be aware that you can get the same size line with all different thread sizes..
heres a example...all 1/4 tube ..different nuts..https://www.summitracing.com/search?...%20flare%20nut
i used 3/16 and 1/4 in brake lines on my truck...and they all have the same size threaded inverted flare nuts...a good flaring tool is not a cheap investment,,but well worth the money...
i have the eastwood version...
i bought all my lines as premade 6ft lines from oreillys..and then cut to length and reflared
__________________
Mongo...aka Greg

RIP Dad
RIP Jesse

1981 C30 LQ9 NV4500..http://67-72chevytrucks.com/vboard/s...d.php?t=753598
Mongos AD- LS3 TR6060...http://67-72chevytrucks.com/vboard/s...34#post8522334
Columbus..the 1957 IH 4x4...http://67-72chevytrucks.com/vboard/s...63#post8082563
2023 Chevy Z71..daily driver
mongocanfly is offline   Reply With Quote
Old 05-03-2019, 01:53 PM   #5
The Rocknrod
Moderator

 
The Rocknrod's Avatar
 
Join Date: Aug 2011
Location: China Spring, TX
Posts: 7,280
Re: Brake line fitting size

Sorry - mongocanfly is correct! you "may" have different sizes depending upon who built the system. The only way to tell for sure is to size them yourself. I just gave the "normal" sizes for the lines at large.
For instance I have 3/16" lines coming off the front and rear ports of my master cylinder, neither of the ports are 3/8"-24. They make nuts for 3/16" lines (or what have you) in various sizes.
The Rocknrod is offline   Reply With Quote
Old 05-03-2019, 02:45 PM   #6
69SCSS
Registered User
 
69SCSS's Avatar
 
Join Date: Aug 2012
Location: Neskowin OR
Posts: 1,153
Re: Brake line fitting size

Thanks guys, measured my line up and it's 3/16" OD, so that solves that, and the fitting measures 3/8" at the hex and slightly above at the threads, so most likely 3/8-24. Going to pick up this line from Summit and it should do the job.

https://www.summitracing.com/parts/aaf-all48302
Attached Images
 
__________________
My 68 SWB
Al Silveira Music
<- My daughter loves this guy 8-)
69SCSS is offline   Reply With Quote
Old 05-07-2019, 08:06 AM   #7
jbarron
Registered User
 
Join Date: Apr 2006
Location: Spring, Texas
Posts: 167
Re: Brake line fitting size

These Parker inverted flare gaskets work great for lines that just won't seal.

https://www.grainger.com/product/5WR...g!540946298555!
__________________
'72 3/4 Cheyenne Super 402/TH400 Gear Vendors
'72 3/4 Cheyenne Super 350/200R4
'50 1/2 Chevy 3 Window
jbarron is offline   Reply With Quote
Old 05-07-2019, 11:20 AM   #8
The Rocknrod
Moderator

 
The Rocknrod's Avatar
 
Join Date: Aug 2011
Location: China Spring, TX
Posts: 7,280
Re: Brake line fitting size

That's interesting. I've never heard of those. Have you had luck with them?
The Rocknrod is offline   Reply With Quote
Old 05-07-2019, 11:53 AM   #9
mongocanfly
Post Whore

 
mongocanfly's Avatar
 
Join Date: May 2015
Location: Alabama
Posts: 14,557
Re: Brake line fitting size

I've never seen those either...but havnt had issues with inverts leaking either..
__________________
Mongo...aka Greg

RIP Dad
RIP Jesse

1981 C30 LQ9 NV4500..http://67-72chevytrucks.com/vboard/s...d.php?t=753598
Mongos AD- LS3 TR6060...http://67-72chevytrucks.com/vboard/s...34#post8522334
Columbus..the 1957 IH 4x4...http://67-72chevytrucks.com/vboard/s...63#post8082563
2023 Chevy Z71..daily driver
mongocanfly is offline   Reply With Quote
Old 05-11-2019, 12:00 PM   #10
69SCSS
Registered User
 
69SCSS's Avatar
 
Join Date: Aug 2012
Location: Neskowin OR
Posts: 1,153
Re: Brake line fitting size

Quote:
Originally Posted by jbarron View Post
These Parker inverted flare gaskets work great for lines that just won't seal.

https://www.grainger.com/product/5WR...g!540946298555!
Thank you for recommending these, they did the trick! Sealed up nice and clean now.
There might have been a burr or scratch inside the Prop Valve that was not allowing it to seal correctly, because I could not get it to seal completely until I used this. Thanks again, I can drive my truck now!
__________________
My 68 SWB
Al Silveira Music
<- My daughter loves this guy 8-)
69SCSS is offline   Reply With Quote
Old 11-15-2021, 11:16 AM   #11
45ACP
Registered User
 
Join Date: Aug 2018
Location: Roseville, CA
Posts: 1
Re: Brake line fitting size

I'm not sure about a few things like if these lines were original or not, but the last 1972 C10 that I changed brakes on, both rear and the right front hard line inverted flare nuts were 3/8 -24, but the left front was 7/16 -24. The flex brake hoses that came with the kit were all 3/8-24 so I used a
Dorman 785-434 line adapter to easily make things work without needing to re-flare any hard lines.
https://www.summitracing.com/parts/rnb-785-434
45ACP is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 08:48 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com