Heater Hose firewall connections -replace, revision, update

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corvette744

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^^^ THIS.

xx343 is the white connector and goes to the heater core pipe that is nearest the driver's side. This one has more of a 90° tee than the black tee. The hose coming from the water pump is the one that has the "y" in it at the WP connection.

xx342 is the black connector and goes to the heater core pipe that is nearest the passenger fender. This one has less than a 90° tee that takes the down connection away from the firewall (angles toward the front of the engine compartment).

Note the different styles of hose connectors that come from the WP.


View attachment 360546
Gotcha checked mine out they seem perfect not sure i should even replace them.Even the hoses look great but i want all the part numbers in case i need them quick.Seems like the numbers on my heater hoses have be changed to new numbers so found 1 on rock auto but not the other-but im sure i will find something
 

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Gotcha checked mine out they seem perfect not sure i should even replace them.Even the hoses look great but i want all the part numbers in case i need them quick.Seems like the numbers on my heater hoses have be changed to new numbers so found 1 on rock auto but not the other-but im sure i will find something
My 2001 currently has 240k miles on it. About 2-3 years ago I had to back flush the heater core because it stopped putting out heat in the front and I figured it was clogged.

These plastic T's were the original ones that came on the vehicle when new and I figured I should replace them for preventative measures while I had them off and ordered new ones before I did the job.

The ones I removed were in surprisingly good condition still, even at 200k miles and 19 years old.

I've heard that these T's get brittle and crack and leak. I guess a lot of it has to do with the environment/climate the vehicle spends it's life in, and how often they're messed with (disconnected or hoses moved/pushed out of way for maintenance of other engine components) and stresses placed on them.
 
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mattt

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My 2001 currently has 240k miles on it. About 2-3 years ago I had to back flush the heater core because it stopped putting out heat in the front and I figured it was clogged.

These plastic T's were the original ones that came on the vehicle when new and I figured I should replace them for preventative measures while I had them off and ordered new ones before I did the job.

The ones I removed were in surprisingly good condition still, even at 200k miles and 19 years old.

I've heard that these T's get brittle and crack and leak. I guess a lot of it has to do with the environment/climate the vehicle spends it's life in, and how often they're messed with (disconnected or hoses moved/pushed out of way for maintenance of other engine components) and stresses placed on them.
I'm in the same boat with 335k miles and they've never given me a lick of a problem. Guess I'll be looking for the GM ones, since as much as the aluminum ones sound like a permanent solution, at the selling price, I'll gamble for another 335k miles with factory ones. Are the plastic fittings separate from the hoses themselves? I had 'mistakenly?' thought the fitting and hose were all one.

I thought I had seen other variations in the past that eliminated the fitting all together, but can't find anything like that now. Thank you everyone for posting here in this thread.
 
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I'm in the same boat with 335k miles and they've never given me a lick of a problem. Guess I'll be looking for the GM ones, since as much as the aluminum ones sound like a permanent solution, at the selling price, I'll gamble for another 335k miles with factory ones. Are the plastic fittings separate from the hoses themselves? I had 'mistakenly?' thought the fitting and hose were all one.

I thought I had seen other variations in the past that eliminated the fitting all together, but can't find anything like that now. Thank you everyone for posting here in this thread.
The end of both hoses have a quick connect that slips over the end of the T fitting. The side of the T that goes onto the heater core pipes and the metal lines that run to the rear heater core slips over the metal tubes and click securely over the barb on the tubes.

There are 2 tabs at each connection that get pressed/squeezed which raise the clip that secures over the barb. I've found that if you push the fitting "on" more, then squeeze the tabs, then pull, the connector disengages.

Remove the hoses first, then the side pipes going to rear core, then the T from the front core.
 

SnowDrifter

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Those gruven ones look.... Honestly, janky? 100 bucks for a T-fitting and they can't even include a good set of constant tension clamps. I would have expected a machined groove and o-ring for the cost. Not a chunk of hose with some clamps. Meh.

I have the stock plastic ones on mine. I have half a mind to think that all the brittle issues are just from running gross coolant. I'm running honda coolant in mine and I can't say I've noted any brittleness. Even when disconnecting the things. Which, by the way.... These pop those off with no fuss https://www.harborfreight.com/fuel-line-and-ac-quick-disconnect-tool-6-pc-63595.html

Not sure I'd re-use them in your scenario. But look at it this way: OEM lasted you until your car got old enough to vote. You really going to have your rig in another 20 years? I mean, really? Not much to complain on there. Don't fix it till it breaks. Grab another set and call it a day
 
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mattt

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Thanks for all the replies here. I'm not going to re-use the original ones. I looked and the hoses are all date coded 06-03 which corresponds with the build date on the driver's door tag. Pretty impressive that factory hoses and fittings have made it this long. So I picked up GM OEM plastic Tee's and hoses a couple days ago and those are going in prior to the new lq9 engine.

Prior to picking up the OEM Tee fittings, I ran across these new ones in a Tahoe at a PYP yard. I have looked online and can't find any info on the part # 20085 that is printed on this Tee. Anyone know what brand of Tee this is?Htrconn.JPG
 

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What are the uncolored characters that are molded into the tee?
 
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mattt

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There are none. Only "Chiiiina"
 
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iamdub

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So I picked up GM OEM plastic Tee's and hoses a couple days ago and those are going in prior to the new lq9 engine.

I'd put 'em in after the engine's in place so there's no risk of breaking them. Being push-to-connect, it shouldn't be difficult.
 

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I replaced these and the hoses yesterday on my 2006 Tahoe. It is a bit frustrating. Get the right side (facing to the rear of the car) first. This allows room to get your fingers on the tabs of the other fitting. After about 1 hour of pushing and pulling I got both off. Strong fingers help. I thought of using a hose clamp to push down the tabs. I didn't try it because thought of it afterwards. Taking the other ends of the hoses off helps because you can turn the fittings to get your finger in a better position. I bought a set of plastic AC fitting removal clips - these didn't help. I cleaned the O ring sealing surfaces with an old fine scruff pad and coated with SuperLube so as not to damage the O rings during install. I used OEM parts bought at my local dealer, I got tired of looking on RockAuto. I paid a huge amount of money for them. Don't care - I don't leaks or doing this all over again. I bought the hoses from the dealer also. They come with the clamps "pre-loaded" which is nice along with the markings to get them installed correctly. So far so good. I'll know later today after a drive.
 

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