Hard brake line diameter?

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dafun1

dafun1

10 Year 15 Year
Joined
Sep 22, 2008
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Location
Bentonville, Arkansas
I need to do some work on the hard lines and I couldn't find the actual diameter of the stock lines. I know the fittings are M10x1.0 but are the hard lines really 10mm in external diameter? They look smaller than that. I've got the metric flaring tool set and wrench set at my disposal. I just want to know what the stock hard brake line diameter is. Thanks
 
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No one knows about the hard brake lines?
 
4.75mm correct?
 
I've got it all figured out now. Stock brake line is 4.75mm OD. The fittings are M10x1.0. Flare ISO Bubble. Torque is 11 ft/lbs. The plan is a complete removal of the ABS and LSPV. I'll replace the LSPV with an engine bay mounted Tilton proportioning valve. The ABS MC will be re-used. I'll start my own thread with pics when it begins. Right now I'm just getting all the parts together.

The Tilton manual proportioning valve will be mounted underneath the MC where the three way fitting once was. The ABS MC has only two outlets, on more forward on top, and on more to the rear on the side. The rear outlet will connect to the new Tilton valve and then to the line running to the rear. The front has two lines and they will be connected to the more forward outlet using a new three way fitting. In the rear, two lines come into the LSPV, with only one coming out in the stock configuration. I'm only using one of the stock lines to the back, and a new tube joiner will connect the single lines. This keeps cutting, flaring and bending to a minimum.

I'm also installing speed bleeders and longer brake lines cause I'm going to 12" travel Doetsch prerunner 8000 shocks soon. I'm really excited about documenting this because no one who has done this has really documented the bypass/removal of the ABS and the LSPV. And I will also be fabricating spring retainers to keep my wee springs from coming unseated.

This has been a fun thread of talking to myself, but I learned alot from the research. Of course no one even threw I guy a bone on this site :clap:.
 
Small tip about Speed Bleeders; the type/brand I used would not seat fully in the rear calipers due to the shape of the tips which made them maybe 1mm too long at that end. They did seat however in the front calipers. In the photos below you can see that the OEM bleed screws have a blunted or cut off tip. Also found that the tightening nut on the Speed Bleeders is set lower than on the OEM bleed screws so when tightening them on the front calipers the wrench would hit a bolt forcing me to change the position of the wrench about every 1/8 turn when installing them. FWIW.
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dafun1 said:
I've got it all figured out now. Stock brake line is 4.75mm OD. The fittings are M10x1.0. Flare ISO Bubble. Torque is 11 ft/lbs. The plan is a complete removal of the ABS and LSPV. I'll replace the LSPV with an engine bay mounted Tilton proportioning valve. The ABS MC will be re-used. I'll start my own thread with pics when it begins. Right now I'm just getting all the parts together.

The Tilton manual proportioning valve will be mounted underneath the MC where the three way fitting once was. The ABS MC has only two outlets, on more forward on top, and on more to the rear on the side. The rear outlet will connect to the new Tilton valve and then to the line running to the rear. The front has two lines and they will be connected to the more forward outlet using a new three way fitting. In the rear, two lines come into the LSPV, with only one coming out in the stock configuration. I'm only using one of the stock lines to the back, and a new tube joiner will connect the single lines. This keeps cutting, flaring and bending to a minimum.

I'm also installing speed bleeders and longer brake lines cause I'm going to 12" travel Doetsch prerunner 8000 shocks soon. I'm really excited about documenting this because no one who has done this has really documented the bypass/removal of the ABS and the LSPV. And I will also be fabricating spring retainers to keep my wee springs from coming unseated.

This has been a fun thread of talking to myself, but I learned alot from the research. Of course no one even threw I guy a bone on this site :clap:.
Click to expand...

I'm getting ready to remove the ABS also. I'm not sure you need a proportioning valve. I only say that because I have been running with the LSPV bypassed and have done several lock up at speed:hillbilly: with great results. Looking at my set up ('96) looks like the OEM lines can be re-routed without adding any other lines. I also plan to re-use the factory ABS MC.

FWIW there has been documentation on removal but deleted.
 
Not to take away any fun but I'd just go out and buy new lines from Toyota for the non ABS 80s and be done with it if that is what you want.

I'm in the process of replacing all the hard lines on a LX from the frame done, 10 in all. The 10 lines with various bolts, clamps was less than 200.00.

And to do what you want there would be only about 5 lines needed.
 
landtank said:
Not to take away any fun but I'd just go out and buy new lines from Toyota for the non ABS 80s and be done with it if that is what you want.

I'm in the process of replacing all the hard lines on a LX from the frame done, 10 in all. The 10 lines with various bolts, clamps was less than 200.00.

And to do what you want there would be only about 5 lines needed.
Click to expand...

I dont see <$200 as chump change...If one can re-use the ABS lines in perfect condition without cutting and install 1 coupling I'm good with that. I can tweak the OEM ABS lines a lot faster then replacing ~5 lines:rolleyes: I see nothing gained by replacing.
 
I'm re-using the stock lines guys, I'm just bending and possibly cutting and flaring again if needed. After looking again this morning, I don't think it will be a problem just bending the existing lines I plan on using. I will only be running three lines using what is already there.

I ordered the bleeders from speed bleeder. Can you flatten the tip 1mm to fit on the rear?

I like the idea of the manual valve so you can dial in more rear brake power if and when you need it. Excellent info though guys. Thanks!
 
I'm sure you can file off the tip so they would seat fully. The seating scuff mark on the tip of the Speed Bleeder (after trying to get it to seat) only went halfway around the tip, so probably wouldn't have to file off much. I ended up using the new bleed screws that came with a pair of Toyota reman'd front calipers for the rear calipers (old bleed screws were corroded badly) and put the Speed Bleeders in the front. After it was all done I realized I could have just filed off the tips but didn't want to dig back into it at that point. Report back if you use the Speed Bleeders in the rear.
 
LandCruiserPhil said:
I dont see <$200 as chump change...If one can re-use the ABS lines in perfect condition without cutting and install 1 coupling I'm good with that. I can tweak the OEM ABS lines a lot faster then replacing ~5 lines:rolleyes: I see nothing gained by replacing.
Click to expand...

I got the idea from his post that he was doing something more than adding a "T" but actually running some new lines. If that was the case then buying OEM is real cost effective and a big time saver.
 
LandCruiserPhil, living in AZ, forget that in the NE we can reuse nothing after 15 years. It is my LX Landtank is working on.

Kernel, I have speedbleeders in all 5 locations and don't remember running into an issue.
 
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I just finished up the bleeding of rhyary's truck and I wasn't able to bleed the system initially with the speed bleeders in place. I'm thinking that there was so much air in the system that it couldn't build enough pressure to overcome the check valves.

I used a stock bleeder at each wheel until fluid was present then swapped in the SB and went to the next wheel. Once all the wheels and LSPV were initially bled the speed bleeders worked great to finish off the job.

My son is the designated pedal operator and commented that the pedal was "ridiculously hard"! He's done more than ten trucks now and drives one so he's a good barometer for a first impression.
 
rhyary: I dug into the parts bin and found the Speed Bleeder that wouldn't work, forgot earlier but I had filed off the tip but it still wouldn't seat or seal completely IIRC. Once I substituted the standard bleed screws in the rear I was then able to completely bleed the system. So I guess I don't know why they didn't work, maybe corrosion at the bottom of the hole??
 
This may be worth mentioning:
When I got the 5 stainless steel SB, about two years a go, one of them did not work. No matter how much I opened it, or how hard I pushed on the brakes, the valve wouldn't open. That was after rebuilding my calipers and I knew the calipers were clean.

I called SB and they immediately sent me another one which worked as it should. So I had 5 working SBs.

This summer I did bleeding as preventive maintenance, four worked great and one would not open. I called SB which immediately sent me another one. They actually found my record on their computer which tells me they are organized.

When I installed that one, it worked as it should.

So twice I had it not working and twice a new one worked with no modification.

It is worth noticing that both times the SB was a rear caliper one.

Might be just me but, I wouldn't modify a brake component. Not even filling the tip.

Sent from my iPhone using IH8MUD
 
Double flare? I thought it was a metric iso bubble flare? Which is it fellas?
 
Thanks Landtank. All my research said bubble flare, and the fittings I ordered are for bubble, so it was going to be a painful mistake!
 
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