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haven’t heard of that, what model and what is wrong?
2003 silverado, 5.3, 155k miles.
i started losing coolant about 2 months ago, just small amounts, then it got worse and worse, yet no leak to be found anywhere.
do some digging online, and find a GM TSB on a small percentage of 4.8 and 5.3 engines, that the heads “develop a porosity crack in a very specific area.” therefore leaking coolant into the head, and then into the oil return.
so, we pulled the valve covers off last night, and low and behold, there is my missing coolant…
so, if anyone with a GM 4.8 or 5.3 from 2001-2006, if you are missing coolant, yet can’t find a leak, you might want to look into this.
http://www.gm-trucks.com/forums/index.php?showtopic=57746&st=30
depending on when the heads show up, i might be turkey hunting out of my Pimpin’ 626 next weekend…