So I am in the process of replacing my Heater Core and I thought I'd examine the HVAC system because it has the common ATF contamination. I am going to replace the actuators. I thought I should replace the lines too while it is all apart.

What I want to know does GM have a part numbers for the actual colored HVAC lines. If so does anyone know them?

 

I had ATF in the HVAC lines on my '98 Jimmy and I sprayed Simple Green into them and then blew them out with compressed air. They have been good as new ever since. Just make sure that the lines are completely disconnected from the actuators when you blow the compressed air through them. I exploded the slave actuator on the passenger's side because I forgot to disconnect it from the line. Luckily it's the slave actuator and it's not necessary.

 

After much searching, calling and digging I came across some stuff. I found the part numbers for a lot of our HVAC stuff.

52494020 - Vacuum Lines
15718298 - HVAC Control Connector (Vacuum line connector that plugs into the back of the HVAC controls)

This is the site I came across that gives part numbers and diagrams of a LOT of vehicles:
Chevrolet Parts, Cadillac Parts, GMC Parts and Buick Parts powered by Nalley Buick GMC | Nalley Buick GMC Brunswick

And here is the specific page of our heater assembly:
HEATER ASM (C | Nalley Buick GMC Brunswick

I hope this helps out people in case they want to replace them.

 

Thank's, it's great when someone comes back with stuff like that.

 

THis does work pretty well. I have replaced rubber vacuum lines, but never the colored lines behind the dash. Those are made of a harder plastic-like material and are not exposed to the harsh conditions of the engine compartment and underside of the vehicle. The colored lines don't seem to break down much, so I've just blown them out with compressed air. My '96 Sonoma that I sold last December still had its original colored lines and the vaccum system was fine after I cleaned them out. But if you're already inside the dash and those lines don't cost much, never hurts to replace them.