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Discussion Starter #1
The time is nearing for a brake job on the truck. I'd sorta like to go ahead and get rid of the abs system while i have the system open replacing calipers and wheel cylinders. I am having problems finding the size of the fittings required for both the master cylinder and then at where the hard lines attach to the soft lines in the front. Also i would like to know the size of the fitting for the rear line disconnect that is located right about where the frame is no longer boxed.

I have been to 3 different parts stores and none really had what i thought i would need. Can anyone give me some numbers? I should be able to post some pictures later.

Thanks in advance
 

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Discussion Starter #2
Here are some pictures to help explain what i am trying to find.

These first two are of the disconnect for the rear single line located right about the firewall. Anyone know the size of this male fitting? I was able to get a caliper on the threads of this fitting and it came out to .43" or 7/16 i think. But i'm not real sure the size of the line.
DSC00131.jpg

DSC00134.jpg


This next is of the disconnect for the passenger side brake located at about the front of the engine on on the drivers side. The diameter of the threads on this fitting was .375" or 3/8. I also don't know the diameter of this line. I think the lines must be measured internally because when i mic'ed the outside i got .2" which is not a standard size.
DSC00133.jpg


And lastly the fittings attaching the lines to the master cylinder. I also put a caliper on the threads of each of these and got .545" or about 9/16" for the front one and then about .475" which i figured was just 1/2" for the back fitting.
DSC00132.jpg



So, anyone have any specs or a helpful website to figure some of these sizes out?
 

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Discussion Starter #3
Ahh, right you are. I want to ditch the whole damn thing though and run a new line from the master to a t for the fronts and a new line back to that rear disconnect i posted. Anyways, next question, i guess the front brake is the rear line in out of the master because that is the bigger reservoir. So when then is the front line so much larger even especially when the reservoir for it is about half the size of the front. You'r think gm would put the larger line with the larger reservoir to move more fluid.
 
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