Hey. My cousin have 2004 Chevy avalanche 130,233 miles. 5.3 vortec Amy told me that it been keep fill up coolant and it keep low coolant. Sometimes no coolant level in there. It been replaced water pump in 3 years ago. I check oil dipstick see if any milky color in there. It's nothing to nocited. So I looked anywhere if there's leak. I put cardboard overnight. Still no show. I asked Amy if she ever get overheat. She say maybe one or two times for a year. It's been one year low coolant. Wonder if you know what it cause? It is impossible if it's head gasket. It would go through oil mix water by now.

Also the service brake system on the cluster say brake and abs light on. How? We did replace front new brake pads. Drove test make sure brake ok. But I did slap brake a little hard somehow cluster start show light and warning.

The climate control. The driver side blow cold and passenger side blow hot. It is climate control panel bad?
Hope you can help me a little. That way I'm try to save Amy time not take it to gm dealership. Save some money. Many thanks for share the comments.

 

Really 38 view with no comment. Anyone not have any problem this issues before?

 

For the coolant issue... I would check the reservoir cap, if it is not allowing the system to build proper pressure it can allow the cooling system to vent while in operation and let coolant vent out of the system in a vapor.

Not real sure about the climate control but I think with the dual climate control there is a way to sync them or atleast a procedure to get the system operating properly after it is disassembled. I would look into that before you start throwing parts at it.

 

Dipstick doesn't always show milky oil. Open valve cover and inspect. 706 Heads have been known to crack around bolt hole.

ABS issue is probably bad ABS module. Very common but need to read code to confirm issue

Climate control issue could be blend door motor. They have been known to stick and have 1 side blow hot 1 side blow cold. very common issue.

 

Yeah I will check blend door motor. I need find a special scan that allow look at abs troubleshooting. Will let you know ASAP.

Really 706 on 2004 model bad design cause crack? I'm wonder about mine since I have 706 on 2006 Silverado. Will crack later or they are better design on model year of 2006? Just wonder. Will able nocited if take valve cover look at any crack area ?

 

Yeah you will have to take the valve cover off to check it and if there is the slightest bit of sludge on the heads it will be hard to see the little hair line crack that can form. Also look gor the milkyness goo that can build up on the underside of the valve cover