Heater Hose "T"

[Blk00ss]

Ok you are blessed then, hat's off to you. So you said the white one on the inboard side was the one that failed? What about the quick connector from the heater hose that clips onto that tee? That bugger is well known to faYeah, after some more reading I think m

Ok you are blessed then, hat's off to you. So you said the white one on the inboard side was the one that failed? What about the quick connector from the heater hose that clips onto that tee? That bugger is well known to fa

Well, I thought it was the white one. When I started to try and disconnect the white one, I noticed the black one dripping. The issue with that is I only ordered a white genuine GM one. But I needed this fixed because my son needs his truck this weekend, and I'm leaving town. So I had to go buy a damn Dorman black one because I have to order a genuine GM black one. Yes I know, the Dorman ones can leak, but seeing as how these ones were the factory 173K ones, maybe this Dorman one will hold us over until I can replace it with a GM one. So basically I have new GM white one and a Dorman black one.

As far as the clips are concerned I actually had a grey one inside the GM heater hose I ordered years ago when I thought it was leaking way back then. That GM hose has been sitting on my shelf for years because back then the leak ended up not being that hose. But to my surprise, it had a replacement (never used) grey clip that clips onto the outboard black "T". Apparently Dorman makes the clips also, PN 800-407. It comes with the small clip and a larger one. So I used the grey GM clip from my heater hose I never used to connect to the black "T" and I used a white Dorman clip to connect to the white GM "T" i used

 

[Joseph Garcia]

I'm glad that your project went very smoothly. You are an outlier, but I'm happy for you.

As stated above, the new Tees should come with a new clip. Mine did.

Remember to replace the Dorman Tee when you gat a chance, because if the Dorman Tee grenades, you will lose 75% of your coolant within 60 seconds.

 

[Blk00ss]

I'm glad that your project went very smoothly. You are an outlier, but I'm happy for you.

As stated above, the new Tees should come with a new clip. Mine did.

Remember to replace the Dorman Tee when you gat a chance, because if the Dorman Tee grenades, you will lose 75% of your coolant within 60 seconds.

Yeah I will. Yeah, neither T came with the clips that bring the hose from the pump up to the T. It had the clips that go onto the core and the steel lines, but not the clips that go inside the hoses that connect at the front of the T's.

For anyone doing this job, I found it helpful to twist the connections a bit. On mine you could actually hear and kind of feel as if it was breaking a seal. I'm sure after all these miles those plastic Ts try to become "one" with the steel lines and the core connection

 

[ScottyBoy]

I replaced both my T's and the quick connects that plug onto the T's, all with Dorman parts. I replaced them all back in 2017 and so far they are still holding up just fine. To remove the old ones, I literally used a flat blade screwdriver, a utility knife, and some small *****/wire cutters. I tried the actual release tool but with it being so close to the firewall it's damn near impossible to get the tool in there to release the tabs. So I started cutting and hacking away at the old T fitting and removed it in small chunks until I got it all off. Another tip I read somewhere: use Silicone paste/grease (same stuff you lubricate brake caliper slide pins with) to lightly lubricate the O-rings on the new parts and they will slide on easier and be less likely to leak. Just don't use petroleum based grease, it can degrade rubber parts like O-rings, and be sparingly with it, you don't want blobs of it to get into the cooling system.

 

[Rocket Man]

Yeah I will. Yeah, neither T came with the clips that bring the hose from the pump up to the T. It had the clips that go onto the core and the steel lines, but not the clips that go inside the hoses that connect at the front of the T's.

For anyone doing this job, I found it helpful to twist the connections a bit. On mine you could actually hear and kind of feel as if it was breaking a seal. I'm sure after all these miles those plastic Ts try to become "one" with the steel lines and the core connection

I replaced mine and was messing around with the one that had a quick connect hose end that connected to the T- I was able to remove that section in one piece because I didn’t need to disconnect it. This allowed me to play with releasing the thing, then clicking it back on, and releasing it again. I noticed that if you squeeze the tabs and then twist, the connector itself holds the tabs in because they’re not in their release slots. Then just don’t turn it back to its original location and the tabs won’t snap back out. Just wiggle and pull. I tried this with the new hose where it connects to the T ( I had already installed all the new parts by now) and it worked great. If anybody else is doing these, please give this trick a try and lmk if it works for the T’s because I think it will. I just don’t know if there’s enough room to twist them.

 

[MassHoe04]

I replaced mine and was messing around with the one that had a quick connect hose end that connected to the T- I was able to remove that section in one piece because I didn’t need to disconnect it. This allowed me to play with releasing the thing, then clicking it back on, and releasing it again. I noticed that if you squeeze the tabs and then twist, the connector itself holds the tabs in because they’re not in their release slots. Then just don’t turn it back to its original location and the tabs won’t snap back out. Just wiggle and pull. I tried this with the new hose where it connects to the T ( I had already installed all the new parts by now) and it worked great. If anybody else is doing these, please give this trick a try and lmk if it works for the T’s because I think it will. I just don’t know if there’s enough room to twist them.

That's a great tip to keep in mind!

 

[Darrski27]

Thanks for all the info! My black one just started leaking. Dumb question, is it possible to replace them without draining all the coolant first? Trying to avoid more work if it’s not necessary.

 

[MassHoe04]

Thanks for all the info! My black one just started leaking. Dumb question, is it possible to replace them without draining all the coolant first? Trying to avoid more work if it’s not necessary.

The connections are up high in the system, so you shouldn't lose too much. Top off the reservoir when done and check again after running a few trips at temperature, in case it burps any air out. Top off as needed.
You can try to keep the loose end of the hose pointed upward (at least at an angle above horizontal) while the fitting is replaced, to keep all of the coolant in the section of hose from pouring out.

 

[89Suburban]

The connections are up high in the system, so you shouldn't lose too much. Top off the reservoir when done and check again after running a few trips at temperature, in case it burps any air out. Top off as needed.
You can try to keep the loose end of the hose pointed upward (at least at an angle above horizontal) while the fitting is replaced, to keep all of the coolant in the section of hose from pouring out.

Yup. You can also pinch the hoses shut.

 

[5strmtrp]

Wasn't sure where to post this. Our '05 Tahoe has sprung a leak. Its coming from the white "T". I did get a new GM "T". Any advice on getting these off. I realize they have clips you squeeze, but me and GM don't have a good history with these clips. I know many people fail with these because they don't push in first, then pull off. But based on lots of reading it seems this job kind of sucks especially with how close it is to the firewall and under the windshield. Just looking for any tips ya'll might have


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The black one snapped clean off today on my son. Weird thing is it also has a compression fitting on the hose that goes down to the water pump. All suggest the GM one, I see the part #’s here. Gather the white one is around the corner to fail as well. They are a pain in the butt to disconnect. ???The new fittings they come with the plastic tabs or do I need to order them as well??? This truck needs to be back up n running like 4 minutes ago.