Service Tips: 1992 SSEI rear brake line replacement
Ok this one is for the real die-hard who loves to work on his car.
The rear brake lines on my 92 SSEI were all rusting away, and I wanted to change them before they started leaking. I planned this out, getting the parts ahead of time.
I also needed new proportional valves, they were in sad shape too.
Take a piece of string and use it to approximate the length of the existing lines. Follow every bend, then measure with a tape measure. I like to make an exact duplicate of the original lines.
In general, you use brake lines with the metric style bubble flares and metric threads. Don't be temped to use the ones with US threads, they seem like they will work but they do not really fit correctly. AutoZone had some good lines, I think the brand was AGS. They were green in color. They make all types, so make sure it is the right one. I think they called it the European style. I believe the prefix on the part number was AZE.
The tube from the left rear prop valve to the rubber line was done with one 20 inch section, no problem. The right hand side was done with two long sections, joined with a coupling. The coupling is sold by edelman. I think it was 10mm bubble to 10mm bubble flare. You want to plan it so that the coupling ends up in an area that you can reach.
The front of the proportional valve uses a larger sized nut than the others. I assume this is to keep you from installing it backwards. If the nut is ok, you can re-use it. I purchased new ones from GM. At first they will tell you that they can't get them, but if you look at the illustration, lo and behold there they are with a little arrow pointing to them.
I didn't want to replace the line all the way up to the front of the vehicle, there was no need. Some people use those compression fittings to splice the tubing, I would stay away from that.
I have a tool to make a standard inverted flare, so I flared the stubs on the car, and then I used a new piece of tubing with a bubble flare at the prop valve, and then cut that line and made my own flare at the other end, and used a standard inverted flare coupling and nuts to connect to the existing lines. Lots of fun flaring the tube on the car with brake fluid running down my arms. Don't let the fluid reservoir run dry or you are in for a big bleeding exercise.
Just let the fluid bleed from the connections to the rubber lines, and you will not have to touch the bleeders on the rear cylinders.
This job took me about 10 hours, to exactly duplicate the lines and install them. Some day maybe we will be blessed with stainless steel brake lines. Until then, get out the tubing bender. I use the type with a small wheel on the end, and it has handles like a pair of pliers. The gentle bends can be done by hand. The one that looks like a spring that you put around the tube is useless.
By the way GM does not sell any of these pre-formed lines. It'* a darn shame.
Hope this helps