Got the line replaced. The rear fender liner gives no additional access - fuel tank has to be lowered.
It goes without saying that the less fuel you have in the tank before starting this, the better. Although if you've got a full tank, and you're doing this due to the brake line, the vehicle can't be safely driven, so prepare to siphon the tank, if needed. Or be very careful. Fuel weighs about the same as water (~ 8lbs / gallon, so if you have the large tank, that's about 185 lbs of gas, if full)
This worked for me... (and a reminder that it's
only for LWB - the 360s use a tee on top of the pumpkin to connect two smaller length lines together)
Need:
Safety glasses. Rust is everywhere, and it WILL fall into your eyes (and nostrils, and maybe even your ears & mouth.) Big, honkin' chunks of it.
Tank bolts: 15mm socket, probably a breaker bar or impact gun (I used both). And PB Blaster.
Fuel hoses: 7mm socket or wrench, to undo clamps, flat screwdriver or pick tools to break hose seals.
Bracing, jack stands, or two jacks (to hold the tank in place).
You do NOT need to disconnect the front hoses from the tank, or evacuate the fuel system (although it would be good practice to do so (pull fuel pump relay, depress Schrader valve on driver's side fuel rail to relieve pressure)).
Some time before you start this process, spray the frame crossmember bolts. There are holes in the side of the frame near the bolts; use them to spray the bolts from the inside. Also spray the two bolts holding the tank straps in place (front / rear).
Jack up rear of vehicle and place on stands. Retrieve jack. Lower & remove the spare tire. You don't have to remove the rear wheels, but you'll have more room to work if you do.
Use the 15mm socket to remove the four (4) crossmember bolts. If you live in the rust belt, expect that at least one of the four bolts will break, due to corrosion (and if they don't break, the bolts will be corroded, themselves). Hopefully you don't break both bolts on one side.
Loosen (but do NOT remove) the two tank strap bolts (also 15mm). These will be stuck as well.
Position your jack under the front of the tank and lift it so that it will support the tank (or about 1 inch away, maximum). Now remove the front tank strap bolt. If you don't have a second jack, brace up the front of the tank, and move the jack to the rear of the tank. You probably won't be able to lower the front of the tank until the rear strap is removed. But the most you'll want to lower it is about 1" to 1.5", total. If needed, brace things up, and come back to it later.
Before removing the rear tank strap bolt, this is a good time to disconnect the rubber fuel inlet hose from the metal filler line (much easier than disconnecting at the tank end).
Note that if you want the metal filler line to be able to move, there is a speed nut holding a bracket down on the top of the frame (not visible). Remove the speed nut, and lift up on that end, then pull backward to free the front of the bracket (which uses a tab/slot arrangement.) The metal filler line will now move (note the grounding line that connects to the framing for the spare tire - if you break it due to corrosion, remember to reattach it, as it is a safety feature.)
(BTW... If your metal filler line is corroded, this is probably a good time to put in a replacement)
With the fuel hose disconnected, take a look at the top rear of the tank. You'll see two harnesses / plugs, one on each side. If you can get to them now, go ahead and disconnect them, otherwise, you can come back to them in a minute. You don't need to remove the assembly that the right harness clips to - its bracket is attached to the tank.
(If you decide to siphon the tank (I didn't, but I only had 1/4 tank of fuel), now's the time to do that, through the now-accessible fuel inlet)
Position your jack at the rear of the tank, and lift it into place so that it supports the rear of the tank. Now finish removing the rear tank strap bolt. Keep in mind - as soon as this second bolt is removed, along with the strap, the tank will start coming down! Be prepared.
It's hard to remove the rear strap without removing the driveshaft, but it can be bent backward and left hanging in place. That's what I did. (If you decide to drop the driveshaft, those are 11mm bolts.) I also bent the front strap backward a bit, btw.
At this point, you can either lower the rear of the tank, or brace it up and lower the front. I did lower the front of mine about 1-2 inches, before I lowered the rear.
When lowering the rear, you'll need to lower it at least to the 'seam' on the side of the tank, level with the bottom edge of the frame. It can be lowered more than that, but that's the minimum (that's about 6" or so). Do not lower more than necessary to disconnect the two harness plugs, if they're still in place. The harness that connects to the fuel pressure sensor on the right side has a retainer clip above the top of the tank; I disconnected it, but you might be able to get away with just unplugging the connector & leaving that harness retaining clip as-is.
You'll also need to move the rear of the tank inboard (toward the passenger side) 1-2 inches, to have room to remove the last of three (3) clips holding the brake line in place. The other two are on the passenger side (trace the line from the caliper about 12" upward to see it), and almost directly midpoint of the truck. You can see both of these from the passenger side; the last one is in the 'corner' of that rail, and it's obscured by the tank until it's dropped. You'll need a pick tool or a flat screwdriver to pry the round pin up in the middle; the clip can then be pried from the upper rail. The clip opens from the non-hinged side (it's similar to the one that attaches the front brake hose to the bracket on the front knuckle, but I waited until I had the line out (since I didn't know how to release the lock). Note that the plastic tab that locks the clip does not move easily; I wound up just prying the thing out from the outer end (it doesn't break the tab, and although it loosens up a bit to reuse it, it'll hold the new line in place just fine.)
If you haven't already removed the fittings on the brake lines, now's the time to do so. 15mm wrench (line is best, of course). If the fittings are corroded, you may need a pair of vise grips to get the fitting off, if you round off the nut. My passenger side was fine; the driver's side (where it connects to a 'tee') was the bad side. But I got it off without destroying the tee.
The line...
I used a preformed line from a kit I got on eBay (the ONLY place I could find one for LWB). Here's a link to it:
2002-05 Chevrolet/GMC Trailblazer EXT/Envoy XL 4x4 4 Wheel Disc w/ ABS Complete Brake Line Set 8pc (Includes Union), Stainless. Brake Products. 1997-99 Buick Century Rear Drum w/Four-Wheel ABS Rear Axle Brake Lines Kit Steel.
rover.ebay.com
Note that while you get a 'complete' kit (all lines), it is
not cheap - about $170 shipped. While the vendor is in the US, and has an external website, this kit is only available for the LWB through the eBay site - it's not listed on their business site (but the kits for the SWB are, IIRC). Good quality (made in US, on CNC machines), and the fittings are correct (see the post I referenced above for info on them - GM uses oversized fittings, relative to the tubing diameter)
I also had to make the 'last' bend on the driver's side - about two (2) forty-five degree bends, along with bending the end 'up' slightly to reach the tee. But it reached OK. If you don't have a tubing bender, take a deep socket and hold it in place where you want the bend. This will create a smooth enough radius for you. On the passenger side, the line touches the frame - either put in something to keep it from rubbing, or bend the line.
While the kit seems to be adequate, if you know how to make brake lines & have the flaring kit, you may prefer to do this over spending $170 on the kit (and having to make minor bends anyway).
So... whether you buy the preformed kit, or make your own... the way to get the line out & back in is via the passenger side. Note how the line feeds above the trailing link and in back of the exhaust hanger when you pull it out. It needs to go back in the same way. Getting it routed through on the tank side was not terribly difficult.
Fasten the center retaining clip in place, but do NOT 'lock' the two side clips, lest you have to bend the line to fit it properly. The amount that I bent the driver's side line meant that I couldn't lock that side's clip back in place - but it's sturdy and doesn't rub against anything.
Screw in the new fittings (I did the passenger side first). Then put the tank back in place & reconnect everything. From there, you're ready to bleed the lines (the rear bleeders are in the front of the caliper and can be seen / reached without taking off the wheels, if you still have them on.
And with that... you're done!