Heater Hose firewall connections -replace, revision, update

[mattt]

I have the engine out of my 04 Tahoe currently. It's being replaced with a 6.0 lq9. I seem to have read that the plastic heater hose Q/D's at the firewall tend to be a problem at some point, so I'm thinking about replacing them now. Mine have never leaked or caused any problems but the access to them now is about as good as it gets.
Are there any aftermarket options or updated/upgraded options that are a better way to go than the factory plastic Q/D fittings and heater hoses?
With the engine out, are there any other things that would be best tended to now, before the new engine goes back in? Thanks in advance.

 

[rockola1971]

Dorman makes replacements. Replace them, they dry out and become very brittle and snap. It much les painful doing it with the engine out! Clean connection, replace ground strap if needed behind engine on firewall. I got mine from rockauto for my 05 Denali. Cooling hooses that come up to the T's also have a molded male fitting. Break it off (on purpose) and buy the Dorman "fix" for it. That oem plastic male fitting dries out and becomes brittle also.

 

[swathdiver]

I have the engine out of my 04 Tahoe currently. It's being replaced with a 6.0 lq9. I seem to have read that the plastic heater hose Q/D's at the firewall tend to be a problem at some point, so I'm thinking about replacing them now. Mine have never leaked or caused any problems but the access to them now is about as good as it gets.
Are there any aftermarket options or updated/upgraded options that are a better way to go than the factory plastic Q/D fittings and heater hoses?
With the engine out, are there any other things that would be best tended to now, before the new engine goes back in? Thanks in advance.

Gruven made a run of metal ones specifically at the behest of a forum member here, Ken. @kbuskill

 

[gooffeyguy]

Go with either the OE GM ACDelco ones (about $25 each} or the Gruven billet ones (about $75 each), not the Dorman ones. They've been reported to break/crack prematurely.

 

[corvette744]

Go with either the OE GM ACDelco ones (about $25 each} or the Gruven billet ones (about $75 each), not the Dorman ones. They've been reported to break/crack prematurely.

Got a part number for the factory ones.Found the gruven their 95 bucks and would need 2 no thanks.

 

[gooffeyguy]

15055342 and 15055343

One is the inlet side, the other is the outlet side, not sure which is which.

There's two different ones because the angle of the auxillary (rear) heater pipes are at different angles.

 

[89Suburban]

Transitional Hose Tee

Transitional hose tees can be used for custom cooling system hose connections.You must choose the measurements for the three hose sizes A, B and C. Choose A and B from the pulldowns and enter C in the space provided. C sizes could be anything from 1/4” to 2". NOTE: If you need a size not listed...

jagsthatrun.com

Billet GM Heater Core Coolant Tees

Welcome to Gruven Parts, your online home for custom auto parts.

www.gruvenparts.com

 

[S33k3r]

Now might be a good time to check, clean, and/or replace all grounds in the engine bay. You may also want to replace the main lead between the alternator and the fuse box. I've read about cases where that wire corrodes inside.

Read up on "the big three".

Check all your radiator hoses, replace as needed.

Might want to replace the soft lines coming from your transmission to the radiator.

Now would be a good time to acquire a catch can, and maybe add an external transmission filter.

If you're adding efans, do that now.

If you are going to do a hydro boost conversion, now would be good.

Check out your power steering pump and the shafts between your steering wheel and your front wheels.

Got any suspension components that need attention? At least check right now. Maybe even consider a changeover to coilover shocks.

Check for any rust, clean up and paint the surfaces.

Check your AC components.

Check your evaporative system components.
Check your transmission and your transfer case -- especially your transfer case, due to potential pump rub.

Now is likely a good time to check all your engine bay wiring, to make sure it isn't brittle, worn, etc.

Well... That was a longer list than I had anticipated... Sorry about that.

 

[Joseph Garcia]

OEM or Gruven 'Tee' replacements. Do not use anything else.

 

[Fless]

15055342 and 15055343

One is the inlet side, the other is the outlet side, not sure which is which.

There's two different ones because the angle of the auxillary (rear) heater pipes are at different angles.

^^^ 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.

 

[corvette744]

^^^ 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

 

[gooffeyguy]

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.

 

[mattt]

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.

 

[gooffeyguy]

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]

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

 

[mattt]

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?

 

[Fless]

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

 

[mattt]

There are none. Only "Chiiiina"

 

[iamdub]

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.

 

[2006Tahoe2WD]

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.