Question about GMC Envoy XL

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Rear heater core leaking, and causing over heating

On my 2003 envoy xl, the little rubber tube attached to the bottom of what seems to be a rear heater core, is leaking anti-freeze and sometimes causing the vehicle to over heat if I don't make sure the radiotor and overflow bottle are topped off.

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Posted on Jan 02, 2017

  • 1 Answer

SOURCE: no rear heat

There is a seperate heater core for the back of the Suburban. It is located behind the right rear interior quarter panel. You have to pull everything back there the heck apart to get to it. The blower motor is located in the same area, so if you should be having any issues with it, plan on doing them both at the same time. Also, you have to drain the whole coolant system, so if you need to do anything with the front heater core (doesn't sound like you do), plan on doing that at the same time too. Good luck!

Posted on Dec 21, 2008

  • 96 Answers

SOURCE: overflow tibe on radiator is connected to

Its goes radiator-hoes-expantiontank-hoes

Posted on Aug 31, 2009

  • 64 Answers

SOURCE: my vehcle oer heats and leaks anti-freeze

Its hard to figure this one out, without looking at it. pressure test the system pin point the leak, it could be your waterpump. hoses thermostat housing. freeze plugs, head gasket, radiator.

Posted on Apr 17, 2010

  • 324 Answers

SOURCE: rear heater core line leaking, can I fix w/ rubber

yeah hose and clamps are the cheap easy way to go there, or if your lucky, the leak is right at the spot where the hose meets the metal and you can just cut the end off and put it back with the old clamp

Posted on Jun 27, 2010

  • 4 Answers

SOURCE: I have a 2002 GMC Envoy XL that blows cold air

the heat accuator could be bad. It is a motorized part that adjusts your temprature by allowing cold or warm air flow when you adjust the temprature at the knob you are turning

Posted on Jan 21, 2011

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