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Leaky tranny lines...

Guys, you could make this a DIY sticky if you want. Sorry no pics but I'm a dinosaur without a digital camera.

Ok, I installed the lower hose last Sunday. 4 hr job but now that I know how, it could be 2 to 2 1/2 hours. Here's how:

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.
 
Well, add me to the list of people with leaking transmission lines. At least one of them that is, the one that is visible in front of the plastic skid plate.

Yay...:mad2:
 
Be sure to do the permanent fix. It will save you in time and aggravation in the long run. Do it right once and be done with it!
 
I went to Aeroquip and used the size 12 SS braided hose along with the good high quality fittings. A little over kill, as they are good for about 1700 PSI. The size 12 hose is a full 5/8" inside diameter. I still have not hooked them up as I am waiting for weather a little warmer. The ends are flareless compression fittings. I can hopefully do the install without taking the hoses completely off the truck. Do it while the hoses are still in place. I also bought a small mini tubing cutter. I will take photos as soon as I do the install. Complete costs was about $200 for everything.
 
To me, the downtime at the dealer, and taking days out of work hurts more than the $200, one and done fix. I can't afford to keep taking days out of work to go to the dealer for them to fix the hoses with the same lame ass piece of shit crimped hose, so it can leak again.
 
Not disagreeing with you... If it's $200 for the parts then so be it! I have the advantage of OEM prices on Aeroquip and Parker stuff so my perspective may be skewed. If I hadn't already bought the replacement I would have gone that other route. I'm not real sure how well those compression fittings are going to work on the aluminum tube over time but from an ease of replacement standpoint, it sure as hell is better than what I went through... Still not leaking though................yet!
 
Here is my fix for the leaky lines. I used SS Braided Hose #12 with all the fittings. Hose is rated for -100 F to 500 F, 1700 PSI. I have not installed them yet, but they are all made up.

Just noticed mine were leaking today.

Did you have these made or did you do it yourself?

Do you have the aeroquip part numbers?
 
mine just started leaking about two days ago , im seeing drips coming from the pass side front skid plate and the mileage is about 57,000 and the dealer said that im out of my warranty but I bought the extended warranty
 
I've only got 31K on the truck so mine are likely covered under warranty, but I think I might just fix them right so I don't have to do it again.

Plus after today it looks like GM needs the money more than I do.
 
They aren't covered under the 100k D-max/Alli warranty are they?
Belts and hoses in the fine print

mine just started leaking about two days ago , im seeing drips coming from the pass side front skid plate and the mileage is about 57,000 and the dealer said that im out of my warranty but I bought the extended warranty
Belts and hoses in that fine print also
 
So that's a yes? I think when we take it in for the Service Brake system light that hasn't come back on, I'll have them replaced.
 
Unless you have deep pockets, I wouldn't have GM replace the lines if they don't want to do a 'goodwill' replace under warranty.
 
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