4 Wheel Drive/SUVs: 1999 Chevrolet 2500 Suburban 2500 - heater hose leak, dexcool antifreeze, hens teeth

Question
Matt- You're the best! Another one came up yesterday with my brother's '99 suburban 2500, 7.4 L, w/115k miles. It has a leak that appears to be from the upper heater hose where it has coupler/connector, into a screw-in fitting into the front of the intake manifold. All of the top end gaskets were replaced less than a year ago trying to find the culprit. Now, I think "we" found it. I've heard that the screw-in fitting has a tendency to corrode from the inside(apparently GM can't afford stainless steel or brass), and the fitting can break if removed with a socket or wrench once the hose is uncoupled. The coupler connection point has a plastic collar. I'm assuming there is an O ring or some other type of seal between the two components that is failing because of corrosion of the screw-in fitting. Two questions - Is a special tool required to uncouple the connector? If the bottom fitting has to be changed, does that also require a special tool, like a gadget the grabs the fitting from the inside? OK, third, anything else I need to know, like is this screw-in fitting like hens teeth and a dealer order only part, or will most decent parts stores carry it?? We have a huge NAPA warehouse nearby, even open on Sunday.

Answer
Joe, I appreciate the compliment!

Now for the fitting, you are correct and GM did have many issues with corrosion due to the Dexcool antifreeze (Orange) used in their models. Now for the removal if the metal pipe, No special tools required there will be two plastic tabs sticking out of the top of the fitting straight across from one another. You may need to use a pair of channel lock pliers of equivalent to press them together but that's all you have to do, press the together towards the pipe and pull out on the pipe and it will come out. Removing the fitting is a little trick when they are weak but not too bad. A wrench or socket will work but they do have a tendency to break just go easy on it and work it back and forth to try to release the thread lock glue. Just take your time. And for finding the fitting, as I said before they had plenty of issues with these fittings and you can get them at about any auto parts store. They will come with the fitting and the plastic piece that fits over the end if the pipe itself to ensure a good seal.

I hope all goes well with it and like I said , take your time and it will be a piece of cake