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Replace Lower Trans Cooler Line (LBZ)

btfarm

America First!
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This was on my '06 GMC. Took 4 hrs but with this it might be 2 1/2 or so.

1st you'll need:
New retainer clips (3 or 4). I didn't lose one but can see it happening.
Several fender liner fasteners. You'll ruin a few.
Plastic or vinyl caps (1/2") to go over the tube ends to keep crap out.
3 or 4 qts of DexIV or what you use.
Lots of patience...
Full set of tools beyond the normal Sears set.

Jack it up and take the RF off. Remove the front 1/2 of the fender liner and tie it back. Remove the splash guard in front of that. Take out the air box (it just pops out with a good tug. Remove the airbox mount plate and L bracket it mounts to (1/2 doz or so M10 head bolts). Pull the double U shaped plastic clip that holds the 2 lines apart (from underneath) at the back of the radiator. Pull the clip at the trans with a small pick and pull out the line. It will drain about 3 qts over time. At the side of the block is a bracket that holds the 2 lines. Use a small 1/4 " ratchet and 10mm socket to loosen the nut above it and spin it off by hand. Pull the clamp down and rotate it until you can get a large blade screwdriver into the split at the top of it to pry it apart. Make sure the rear 1/2 of the line moves around freely. Pull the front clip at the radiator. It's right between the lower hose and the CAC return line and really tough to get to. I used a small electrician's screwdriver to pry it up enough to get a pick with a hook on the end under it so as not to lose it. Grab the hose from below and wiggle it around until you can jockey the hose end out of the radiator. I think I used a wooden stick to gently pry it. It will drain about a pint. Slide under and look up where the lines go through and you'll see a triangular shaped opening where the double U shaped clip was. The line will come out fairly easy if you cross it over to the other side of the return line and snake it down while working the hose area and rear line around. The whole assembly comes out the back over the steering arm, axle and crossmember. Put the new (preferred) or used clip in the radiator fitting and make sure the detents are all the way into the 3 slots. Put some caps over the ends of the new line to keep the inside (and outside) clean and put the line back in the same way you pulled the old one out. Once you have it located, pull off the front protective cap, start the fitting into the radiator nice and square. When it looked about ready to go in but I couldn't get any leverage, I put a short (3/8 x 1 x 6") piece of wood square to it and gave it a tap with a small hammer. It will click into place. Slide the double U shaped retainer back up there and reinstall the block support bracket. Put the clip into the trans fitting in the 3 slots, pull off the end cap and push the tube in. Put all the rest back together and dump in a couple of qts of DexVI (or what you use) and fire it up. I wound up using 3 qts total after it was up to temp. This was an '06 GMC LBZ so the Chevy trim and an LLY may be somewhat different. I think the leakers was an LBZ thing anyway.
 
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