The good old coolant connectors

[redhat]

Tahoe and Suburban's can have rear heat with plastic/nylon tees at the firewall and the majority of GM trucks use a plastic Y connector to join the heater core outlet hose and surge bottle to water pump.

The later failed on me the other day. Was driving and saw steam coming from under the hood. Pulled over and found the Y connector was cracked and spraying.

Decided to replace it all. Replaced the Y connector, heater hose quick connect and corresponding hoses with the Dorman OE-fix 626538. Includes the hoses, quick connect and a metal Y connector.

Also replaced the other heater hose (inlet) and another Dorman heater hose quick connect (800-403). I had two GM Genuine new heater tees sitting idle (15055342 and 15055343), swapped them out. Luckily, I did, as when I put some pressure on the return tee fitting (white), it started leaking coolant from a hairline crack. See picture below, you can see the crack going at a diagonal.

Topped 'er off with some 50/50 premix of Peak 10X. All in all, good to have them all done for the peace of mind. Both new heater hoses, all new Tees, new Y connector and new quick disconnects.

 

[Lubener]

I never could understand why engineers incorporate plastic components in a cooling system. It's all about $$.

 

[jetman]

I had a plastic heater hose T break a few yrs ago on our 07 Yukon Denali. Replaced both Ts with Gruven.com metal units. I also replaced the hose with the Y with Dorman# 626-553.

 

[redhat]

I had a plastic heater hose T break a few yrs ago on our 07 Yukon Denali. Replaced both Ts with Gruven.com metal units. I also replaced the hose with the Y with Dorman# 626-553.
View attachment 149691

I wanted to do those, they look like nice pieces. But time crunch and the $200 bill for them is a little steep. But probably worth it.

 

[redhat]

I never could understand why engineers incorporate plastic components in a cooling system. It's all about $$.

These spectacularly blow apart at the most terrible time too.