Do our 99 Yukon SLT's have 2 heater cores??

[knoslf]

Okay some of you know i've been having major heating issues, I took sunclitcomet advice and ran the hoses directly to the firewall therefore removing the heater shut-off valve and still no heat, so I am going to change the heater core next and was looking on the autozone site and it lists a 'front' heater core and a 'rear' heater core, wtf? The site shows the exact diagram/location for both so I am unclear on which one to get the front or rear, both have different part #'s too...anyone had to buy one? Is it as easy to replace as some people say as far as going under the glove box behind the heater cores black plastic casing? or is it really necessary to drop the entire dash?

http://www.autozone.com/autozone/parts/1999-GMC-Yukon-4WD/Heater-Core/_/N-jd24xZ91sh1?filterByKeyWord=heater+core&fromString=search

 

[SunlitComet]

You only have a front one. But before you get one access it below if possible and see if it is cold or hot.

 

[knoslf]

You only have a front one. But before you get one access it below if possible and see if it is cold or hot.

Haven't actually opened that black cover on the pass side but the cover itself gets hot,

 

[SunlitComet]

In that case ignore the core and everything in the engine area. With ignition on engine of turn fan on lowest speed and move temp gauge back and forth. Do you here the motor directly below the dash moving at all.

 

[knoslf]

In that case ignore the core and everything in the engine area. With ignition on engine of turn fan on lowest speed and move temp gauge back and forth. Do you here the motor directly below the dash moving at all.

Okay im gonna do that this morning, am I listening for the temperature blend door?...will see if i hear anything...

 

[retorq]

I took sunclitcomet advice and ran the hoses directly to the firewall therefore removing the heater shut-off valve and still no heat

Technically that was my suggestion, you made 2 posts, my post #3 suggested removing the vacuum operated valve. Sunlit didn't suggest it until 21 posts later on page 3.

 

[knoslf]

Technically that was my suggestion, you made 2 posts, my post #3 suggested removing the vacuum operated valve. Sunlit didn't suggest it until 21 posts later on page 3.

Lol, yea I see now but I appreciate everyones input, just kinda remember sunlitcomet name better thats all..but it didnt work so Im gonna try somethin else today...

 

[SunlitComet]

Technically that was my suggestion, you made 2 posts, my post #3 suggested removing the vacuum operated valve. Sunlit didn't suggest it until 21 posts later on page 3.

---------- Post added at 11:45 AM ---------- Previous post was at 11:43 AM ----------

Lol, yea I see now but I appreciate everyones input, just kinda remember sunlitcomet name better thats all..but it didnt work so Im gonna try somethin else today...

 

[knoslf]

Okay im gonna do that this morning, am I listening for the temperature blend door?...will see if i hear anything...

Okay, checked to hear something and when I turn the dial to cold I can hear it "click'' but can't hear anything when I turn it to hot(to the right)

 

[SunlitComet]

you mean motor click or knob click. you don't here a servo motor or door moving around? make sure engine is off but key on and fan on low speed to hear better. you got a multimeter around.