Lq4, Coolant In The Oil?

[3800se.]

Alright guys, I don't know jack about the LQ4. My dad's got a 2001 GMC Yukon Denali with a 6.0L (Non-HO) LQ4 in it, and there appears to be dried (red and crystalline) Dexcool under the oil cap. He did mention there were a few times where he checked the oil cap and saw a "milky white" substance under the cap (only after long, 2+ hour trips), so that told me a coolant leak into the oil. It's nothing I would consider life threatening to the engine at this point, but coolant in the oil is going to dry out main seals or smoke bearings eventually.

 

I've pulled apart my Pontiac Grand Prix 3.8L SC multiple times, and know all to well of the lower intake manifold gaskets failing and spilling coolant into the intake runners or lifter galleries. So my question is, does the LQ4 suffer the same issue, or am I looking for something in the front/rear engine cover areas? 20 minutes of Googling and searching on this board didn't turn up much, so I figured I'd ask.

 

Thanks in advance.

[RyanZ71]

Unless your seeing a change in the oil itself as in it being milky or discolored, I'd not worry about it. I found evidence of red stuff on the bottom of my oil cap... just normal build up in my opinion. Oil was fine, never lost any antifreeze.

[ujtruck]

Alright guys, I don't know jack about the LQ4. My dad's got a 2001 GMC Yukon Denali with a 6.0L (Non-HO) LQ4 in it, and there appears to be dried (red and crystalline) Dexcool under the oil cap. He did mention there were a few times where he checked the oil cap and saw a "milky white" substance under the cap (only after long, 2+ hour trips), so that told me a coolant leak into the oil. It's nothing I would consider life threatening to the engine at this point, but coolant in the oil is going to dry out main seals or smoke bearings eventually.

 

I've pulled apart my Pontiac Grand Prix 3.8L SC multiple times, and know all to well of the lower intake manifold gaskets failing and spilling coolant into the intake runners or lifter galleries. So my question is, does the LQ4 suffer the same issue, or am I looking for something in the front/rear engine cover areas? 20 minutes of Googling and searching on this board didn't turn up much, so I figured I'd ask.

 

Thanks in advance.

 

I would suspect Engine Head Gasket