mayhem100
Junior Member
2016 1500 Crew Cab Laramie, about 154k miles, new to me summer of 25.
Plowed my driveway from the storm last weekend (got about 20" here), noticed my ABS was activating a lot and the pedal kept getting softer. After I finished up and took the plow off I saw a pool of brake fluid in the snow so I got it into the garage right as the last of the fluid squirted out. With some help from my kid pumping the pedal I was able to find the leak was in one of the 2 rear lines, right at the 90 degree bend just under the ABS controller. I'm normally a diy guy so I get stubborn about fixing things myself...plus the dealer says rear lines are on back order and his "old school" brake guy who can bend lines and flare ends only works Mon-Wed, so he can't help me at the moment.
So I headed out the garage to try to sort it out myself in the meantime. Since the OEM parts are on backorder I figured why not run a short splice in the meantime and bypass the rotten part as the line is solid at the ABS controller and also is solid along the frame rail next to the manifold. I've done this before with success and can always opt to replace with OEM later when the weather is nicer, parts are available and I don't have the threat of snow. I haven't gotten the truck thawed out yet underneath so I haven't fully traced the bad line past the firewall, but from diagrams I see online, it looks like the two rear lines go aft and stop at a connection under the cab somewhere and not all the way to back axle, I believe its part #3 on the two diagrams below.
So last night I pulled the driver's fender liner, snipped the bad line where its rotten and unscrewed the line from the ABS controller to see what size fittings I need, only to find that from the looks of it, the RAM brake lines have extremely thick walled construction and an incredibly small ID inside the line. My flare tool will absolutely not hold the OEM line OD and I doubt even if it did that I could flare it. See pic below for the line, this is at a fresh cut with a pipe cutter. Very small ID.
So, any advice on what I might do here? I have a coil of galvanized line I can potentially use, think its 3/16, left over from repairing my old 2004 GMC Sierra. But can I successfully and safely use a line that has a significantly lager bore than the OEM line? Or will this create a pressure differential between the left and right rear brakes? If all I'm talking about is a couple flares, the right threaded ends and 5-6 feet of line with a few bends, I can deal with that as long as I'm not going to wind up trading one problem for a new one. My reasoning is telling me that as long as I have the right ID along the way to the caliper, that pressure will sort itself out and this ought to work, but it also tells me that Stellantis put these oddly thick walled small ID lines in for a reason, so is it a performance thing to make the brakes work a certain way or is it to keep them from rotting out sooner or something else?
Any thoughts or suggestions here would be greatly appreciated.
Plowed my driveway from the storm last weekend (got about 20" here), noticed my ABS was activating a lot and the pedal kept getting softer. After I finished up and took the plow off I saw a pool of brake fluid in the snow so I got it into the garage right as the last of the fluid squirted out. With some help from my kid pumping the pedal I was able to find the leak was in one of the 2 rear lines, right at the 90 degree bend just under the ABS controller. I'm normally a diy guy so I get stubborn about fixing things myself...plus the dealer says rear lines are on back order and his "old school" brake guy who can bend lines and flare ends only works Mon-Wed, so he can't help me at the moment.
So I headed out the garage to try to sort it out myself in the meantime. Since the OEM parts are on backorder I figured why not run a short splice in the meantime and bypass the rotten part as the line is solid at the ABS controller and also is solid along the frame rail next to the manifold. I've done this before with success and can always opt to replace with OEM later when the weather is nicer, parts are available and I don't have the threat of snow. I haven't gotten the truck thawed out yet underneath so I haven't fully traced the bad line past the firewall, but from diagrams I see online, it looks like the two rear lines go aft and stop at a connection under the cab somewhere and not all the way to back axle, I believe its part #3 on the two diagrams below.
So last night I pulled the driver's fender liner, snipped the bad line where its rotten and unscrewed the line from the ABS controller to see what size fittings I need, only to find that from the looks of it, the RAM brake lines have extremely thick walled construction and an incredibly small ID inside the line. My flare tool will absolutely not hold the OEM line OD and I doubt even if it did that I could flare it. See pic below for the line, this is at a fresh cut with a pipe cutter. Very small ID.
So, any advice on what I might do here? I have a coil of galvanized line I can potentially use, think its 3/16, left over from repairing my old 2004 GMC Sierra. But can I successfully and safely use a line that has a significantly lager bore than the OEM line? Or will this create a pressure differential between the left and right rear brakes? If all I'm talking about is a couple flares, the right threaded ends and 5-6 feet of line with a few bends, I can deal with that as long as I'm not going to wind up trading one problem for a new one. My reasoning is telling me that as long as I have the right ID along the way to the caliper, that pressure will sort itself out and this ought to work, but it also tells me that Stellantis put these oddly thick walled small ID lines in for a reason, so is it a performance thing to make the brakes work a certain way or is it to keep them from rotting out sooner or something else?
Any thoughts or suggestions here would be greatly appreciated.
