Greetings All!
New to this forum, and new to the GM V6...
Daughter just bought an '06 Torrent with 90K+ miles from a stealership in Zelienople,PA that offered her no extended warranty on this used car.
2 days later it, heater stopped blowing hot, and it overheated... Bubbling in the recovery tank. They offered no "good will" as it was AS IS...

After separating the heads, water drained out from the heads. Note - the water jackets around the cylinders did not drain out. Is this common or should I be looking for clogged ports lower in the block? I also removed the water pump as the ports on that side were blocked full of crud thanks to the Dexcool... Waiting for the manual, parts & headwork to get here.

Also, about the Dexcool, has this formula been improved since the issues i've read about, or should I stay away from it for replacement?

Love the simplistic nature of the OHV!
Thanks in advance.

Stick with DexCool, but make sure you used distilled water when putting it back in. So far nothing has tied this sludge to DexCool itself, but it has been reported that the sludge builds up if there is air, contaminated water (not distilled), or other types of coolant in the system.

Was it the lower intake manifold gaskets that went bad?

I assume that'* a 3.4L? There are a couple of plugs on each side of the block in the center. You can see it here next to where the oil filter goes.

Yes, it is a 3.4 - "Made in China" motor...

The LIM appeared to have seepage on the front (#2cyl) side, between the LIM and the gasket.
The rear (#1cyl) side minor evidence btwn gasket and head.
The rear also had a "crack" on the green seal ring for #5cyl, and carbon seepage on the green ring for #1cyl.

So, the water should lay in the passages - this is normal?

No DEX debate here please. Lets deal with the posters problem

I'm going to guess here that you have a 3800 L36. If so, I'm sorry to say the fix is a new UIM. So a bit over $100 and a few hours of your time. There are a few write ups about dealing with this here in tech info. Infact I just started a thread, I think it'* called, but, but, my engine wont crank.

Those LIM gasket failures are very, very common. As I mentioned, they are not tied to the coolant type used. It is a mere coincidence that many of these failures are in engines that use DexCool.

What passages are you referring to?

I have seen the same failures with non DEX coolant. The problem is the gaskets. Aluminum framed gaskets are your best choice. however LIM gaskets wont fill the cylinders, that'* the UIM. Look on www.rockauto.com for a replacement.

[QUOTE=xtremerevolution;1509197What passages are you referring to?[/QUOTE]

The water passages around the cylinders. Some of he openings at the top deck were plugged up, not allowing coolant to flow into the heads.

I would have thought that these would have drained to a lower point. But the water pump and rad hose are both higher that this point. I guess I'll have to scrape and vacuum out the gunk as it will not drain...

Already ordered Felpro head gasket kit from them.

There is a drain plug on each side of the block for coolant. I meant to post a pic early but forgot. Here it is.