Brake Line Tubing Size?

[hsdropout]

I need to run my brake lines now. I am planning on matching the rear lines to what was existing, 3/16" to new MC with proportioning valve. My question is can I run 3/16" lines to the new front disc brakes from proportioning valve?
I read where possibly it should be 1/4" to new discs.
Anybody have first hand experience with this. Thanks.

[Kim57]

I ran 3/16 line for all mine and I'm running 4 wheel discs. Not on the road yet but I have no worries about doing it this way.
Kim

[RootBeer 6117]

At school we recently fixed a 98 dodge cummins 2500 ext cab that had 3/16 line all the way to the back with rear disc, my 95 k1500 ext cab has 1/4 to the rear drum and 3/16 up front.Their might be some that argue size matters but if a 3/16 line will work on a 2500 cummins dodge I would think it would be fine on a AD truck.
I did a lot of disc brake swaps on 60's Chevy truck and used 3/16 on the front and 1/4 rear.
Joe

[whid]

I did 3/16 to front disc..1/4 to the rear hose tee then 3/16 out to the drums......whid

[solidaxel]

Originally Posted by whid

I did 3/16 to front disc..1/4 to the rear hose tee then 3/16 out to the drums......whid

Me too!!

[RootBeer 6117]

Originally Posted by solidaxel

Me too!!

me three its 3/16 from the T, somedays I wish I had some of the brain cells back.

[hsdropout]

Thank you all for info. I assume you just crank the fitting up snug with no sealer or teflon tape? and keep your fingers crossed that it doesn't leak.

[MrDude_1]

Originally Posted by hsdropout

Thank you all for info. I assume you just crank the fitting up snug with no sealer or teflon tape? and keep your fingers crossed that it doesn't leak.

like the person above me said.. for the lines you need to use a double flare.
no teflon tape. no thread sealer of any kind.
the seal should be from compressing the flare fittings together.. done correctly the threads should not even be in contact with fluid.

if you're adding fittings to something (like a prop valve, caliper, etc) and it has pipe thread, you can use teflon paste. but you should try to keep pipe threads to a minimum. an ideal brake system (like modern OEM ) doesnt have any.

and never use a compression fitting on the brake system.

[RootBeer 6117]

No sir use double flare tube only no compression fittings, you shouldnt need teflon with good ends. you can get a tool kit that you double flare the line with if you have to cut it.Most of the lines I buy at the part stores come pre made in 10" increments, if you hook two lines together use a double flare union.
This is one place you don't want to cut corners.
Joe