Looks like regular ole 1/4" SAE might work. It seems to fit snug in the brake hose but the fitting I removed from the brake hose does not fit into a 1/4" SAE union. Like to get this done without leaking the first time. Thanks.

 

My 01 has 3/16 for everything on the truck ad far as hard lines go

 

Mine has 1/4" brake lines throughout. Brake fitting from a 3/16" line is way too small for the rear brake hose in my truck. Maybe the difference is disks vs. drums in the back whereas drum brakes need more pressure. Mine has rear drum brakes.
Thanks.

 

I have 1/4" lines throughout my truck except the back axle where it splits to each wheel and the lines on the back axle are 3/16th. If it's the fitting that goes into the ABS then GM used a very uncommon nut on there... Here is what I used for the abs side of that line when I redid my brake lines: http://agscompany.com/product/steel-tub ... ted-5card/

 

Thanks!

 

Nope, didn't work. Standard 1/4" tube fitting is too small for my truck.

Cut the tube a short distance downstream from the ABS module, thinking I would be able to disconnect the fitting and tube intact from the module. Brake fluid was leaking out too fast and couldn't find or fabricate a suitable plug, so I cut the tube at the fitting with a hacksaw blade, took it out the fitting with 14 mm six-point socket. Tried the 1/4" tube plug fitting: too small. Quickly cut a stock 12" brake line (BL-412), replaced one of the 1/4" fittings with the one just removed from the ABS module, flared the tube, put a union and plug in the 1/4" fitting end. Found not enough clearance to get it in the module. So I put the tubing bender to it. Screwed the new tube and plug assembly into the ABS module to at least stop the leaking for now. Added brake fluid to the master cylinder a couple times while working the temporary fix so the reservoir did not run dry.

Since I can't find the correct new fittings I'll make a couple adapter assemblies like shown then build a line with 1/4" fittings to connect the two.

 

The link was for the fitting that goes into the ABS module. The reason the 1/4" in plug didn't work was probably because it's a 5/16th size fitting for 1/4 line from what I understand.

I'm pretty sure your truck should be using 1/4" inch lines so a standard 1/4" flare nut should work. I did however end up with a couple pre-flared lines with the flare nuts on them for the rear axle and the nuts had the wrong size thread, I had to cut them and go get the right 3/16" flare nuts with proper thread size.

Are you replacing the entire line from the ABS module to the rear rubber brake hose?

 

Glad to hear it worked on your truck, I'm reluctant to use other than the original fittings in case the replacement ones leak and I have to redo them and/or contend with damaged threads on either the brake hose and ABS module.

Yes, the brake line between the ABS module and the rear brake hose.

Measured the rear fitting, it's M11-1.0. Calculates out to 6.9/16 x 25.4. Close to standard 1/4" brake line fittings which are 7/16 x 24. Front fitting is M12-1.25, which calculates out to 7.6/16 x 20.3. As compared to 1/2 x 20. I suspect the Imperial fittings could be forced to fit but I don't want to chance it.

Tight bend on the front part of the line, original was about 3/4" radius whereas my tubing bender does minimum 7/8" radius. Will have to get a little creative.

Here's the rear adapter that I made. Original fitting on the brake hose end with standard 1/4" brake line fitting 7/16 x 24 (#490496) on the upstream end (no reason why I used the long nut other than I had it handy). Will connect the two with standard unions, fittings (#785462) and 1/4 flexible tubing.

 

Would you know the thread size on the ABS end? I know its a 1/4 tube, I really don't want to use the old ones. Prefer either a brass adaptor or new flare in stainless

 

Got it all put together and fittings tightened. I used a roll of Poly Armour 1/4" steel line, was able to unroll a straight length, flare a fitting on the end, stick a union with tape on it to keep out the rust, and snake it between the gas tank and the frame from the front. Put 7/16" inch rubber hose over the section where it would otherwise rub against the frame rail on the front of the tube before flaring the fitting on the front end. Able to use the original plastic clip on the back end. Drove it around the block and ran some errands yesterday, no leaks, seems to be fixed. Took a lot longer than expected: hunting down the right fittings (nobody stocks everything anymore), and re-tightening leaking fittings a couple times until they were tight enough.

 

Thanks for this post. I am replacing the rear brake line, and I was told the fitting for the ABS module was 1/4 inch tube 1/2-20. I tried threading it, and while a couple of threads will go in (at most) it seems like to get it tight would require forcing it, assuming I could do that with the small amount of room there is to access it. I will have to go out an get a different fitting and see if that works.

 

Hello and good day I'm wondering if someone could tell me what size fitting I need from the box where the brake lines goto underneath in the center of the truck then feed back to the brakes it's not 5/16 it's bigger please help it's a 2008 Chevy Silverado 4.8 l 4X4 with front calipers and drums in the back.

 

Did you ever figure out what the thread size is on the ABS side - I know its a 1/4 tube, but I can't find any info on the Flare nut that threads into ABS. I would prefer to not use the old ones. Also would like to go brass adaptor or stainless flare nut.