99 XLT, where's the rear heater core

[joedmti]

Last year, heat was working in both the front and the rear. Jiffy Lubers changed my oil, and then up-sold me a radiator flush. BAD IDEA!!
After they finished their Power-Flush, I no longer had heat in the front of the truck, rear heat was fine, so I lived w it. This year, no heat in rear.
Did a little research, just found out there are 2 heater cores.
Gonna flush them before I change them. Any idea where the rear heater core is located?
(Put a visual on my blend door this morning, its working)

Checked the front core hoses, one is hot, one is not. I'm guessing the Jiffy Lube power flush moved and then got the gunk stuck in the core.


Any idea where the rear heater core is?

Thanks in advance,

Joe D

 

[Racenut]

The rear heater core is located on the drivers side rear quarter panel. If you take the plastics out of the back on the drivers side you will see the whole setup ( blend door, a/c, heat, blower motor ).

 

[joedmti]

Found it, thank you! Swapped out the rear core, flushed the lines, no heat in rear, none in front. Mechanic has given up on me.....no idea what to do next, (besides go to another mechanic)

 

[KWT2000]

burp the system

 

[Racenut]

+1 for burbing the system you could have a large air pocket.

If that dosn't work, feel all along the lines to see where it gets cold, once you find the cold spot that is where the line is pluged.

When they flushed the lines during the core change, did they flush both directions or just one way?

Does your truck seem to get up to operating temp quickly or does it take a long time? Or does it even get to full operating temp?

Could be a stuck open thermostat which this time of year would make it run cold. I had a truck do that once, it would drop the idle down like it was warming up, but would never get to operating temp so the heater would not work because all of the lines where cold ( coolant was constantly flowing and not building up heat ). Replaced the thermostat and all was working again.

Hope you can figure it out.