Heater Core Connector Tee, Which Size?

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Dustin Jackson

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@Foggy Coming back to this, at the firewall there are 2 - one is a 111mm and the other is 113mm and we need both? I am in the process of doing this on my own Tahoe as well as the Y fitting near the water pump. Seems dorman makes good metal versions of all of them for $15/per these days but the 111mm vs 113mm is throwing me off.
 

Fless

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@Foggy Coming back to this, at the firewall there are 2 - one is a 111mm and the other is 113mm and we need both? I am in the process of doing this on my own Tahoe as well as the Y fitting near the water pump. Seems dorman makes good metal versions of all of them for $15/per these days but the 111mm vs 113mm is throwing me off.

The two tees are different; the angles of the connections to the pipe for the rear heat are different.
 

petethepug

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IMG_2888.jpegJust received the email where he shipped today... I'm guessing they should be here by the end of the week... there are pics of the actual parts on Gruvens website now though...

Found here...
Billet GM Heater Core Coolant Tees - Gruven Parts
https://www.gruvenparts.com/billet-gm-heater-core-coolant-tees/

Here are his pics...
View attachment 225584

View attachment 225585

They will ship as seen with the 2 sections of silicone hose and 4 clamps.

He is sending me hoses that are a little longer so I can cut them to the needed length and let him know what length will be required to ship.

I also went ahead and ordered this metal Dorman Y-connector for the junction at the heater hose/reservoir hose/water pump so that will eliminate ALL the plastic connectors in my system so that I don't have to worry about replacing those ever again or having them crack and leak or break and leave me, or my wife, stranded.

View attachment 225586

Dorman part # 626-553

HVAC Heater Hose Assembly Dorman 626-553
 

Fless

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@Fless Gotcha so I need to buy a 111mm and a 113mm?

Where are you seeing those measurements, and what part of the piece is being measured? It really doesn't matter for this.

You need the equivalent of one of each of what @OR VietVet posted in #21. Whether that's an OE GM one or the equivalent Dorman or other brands, but I would say if getting the plastic ones stick with OE. The newer metal ones from Dorman look like they'd do the job, too.
 
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Foggy

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@Foggy Coming back to this, at the firewall there are 2 - one is a 111mm and the other is 113mm and we need both? I am in the process of doing this on my own Tahoe as well as the Y fitting near the water pump. Seems dorman makes good metal versions of all of them for $15/per these days but the 111mm vs 113mm is throwing me off.
Back when I did this, the only choice in metal was the gruven ones..
Ended up my local dealer kept the GM ones in stock and weren't very
expensive. Mine actually were just fine, but I had my intake off for my
supercharger install and wanted to proactively replace.. The gm's are still on
there now.
The gm parts are just above this post listed. 1 of each...
The dormans in the updated metal are prob a great choice.
I did the new heater hose by the pump with the metal Y fitting also ! as
I figured it was a great melt down point at the time
 

Dustin Jackson

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@Foggy I ended up getting a 111mm metal dorman and a 113mm metal dorman for the firewall and then another metal dorman Y one with hoses for the water pump are. Thanks guys, sorry to come back to an old thread but it had the right people in it I needed

heres my leak

IMG_9759.jpg
 

rdezs

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You can carefully cut that plastic collar off the hose, and replace the hoses themselves... . But with the reasonable price of the Dorman metal y-pipe, it's sort of a no-brainer. As for the plastic tee fittings to the heater core, if you stay with the plastic stay with OEM genuine GM.
The hoses nobody seems to look at until it's a problem are the ones behind the right rear wheel that go to the heater core in the back. The hoses are available with a complete line set.... Rather prohibitive in cost. For that I used a dorman 90° 3/4 in by 5/8 in hose barb..... Dropped the spare tire, cut the metal lines and use a compression fitting and convert to n AN fitting. Makes the flexible section easily replaceable in the future.

IMG_20241129_092703609_HDR.jpg


IMG_20241129_092744379_HDR.jpg
 

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