spoonermooner

2005 2500hd 6.0 ls 130k miles. Just slapped a stage 2 btr cam in my truck. Noticed some overheating issues here and there before and after the cam. Nothing crazy though. Didn’t think much of it until me and my gf were driving home from the fair when a big cloud of white smoke dumped out the back and a milky substance started pouring from the rear passenger side of the firewall. Couldn’t really tell where it was coming from. On the way to the shop the truck locked up… bearings. DAMN. Got the motor pulled and tore it down. The rings were nice and scored up but the block was still good. The most confusing part was that the head gaskets were mint. There had to have been at least a gallon of water in the oil pan. Only after running for maybe 30min total with the “blown head gasket”. I need my truck running asap. Picking up a new crank isn’t an issue. Finding out where the water is coming from is my main concern. No cracks in the heads or block anywhere. Or at least big enough to let in that much water. Head gaskets are mint. All seals are mint. Rings mint. Brand new cam. I’m really stumped here. If anyone knows another place the water could be coming from please let me know!!

strutaeng

The rear passenger area near the firewall? The quick connects for the heater hoses are prone to cracking and leaking near that area. You can just remove them and plug the hoses directly into the aluminum tubing with hose clamps.

Maybe your radiator engine cooler failed and that how you got water in the engine oil?

Did the engine overheat? Maybe the heat caused those quick connects to break and that's the reason why you noticed the mess coming out of there?

Just thinking out loud here...

You can probably check the cooler with compressed air to validate my theory.

RB04Av

Probably a cracked head. Although it's not impossible it could be the oil cooler; OTOH when that goes bad, ALOT more oil usually goes into the coolant than vice-versa, since leeeeeks always flow from an area of higher pressure to one of lower (a corollary of the First Law Of Plumbing), and oil is at 40-50 psi or whatever, while coolant is at 15ish. Not impossible but not likely either, unless the cooling system is also full of oil.

It'd be beyond mere economic suicide to "rebuild" a common, cheeeeeeep, readily available core like a LQ4, that potentially has a fatal issue that you haven't identified yet, when you need the truck back on the road (earning revenue?) rather than serving as a long-term lawn ornament. Best thing to do IMO would be to just pick one up from an organ donor at yer local buzzard nest and forget about the cam for the time being. Take it out and save it for later.

LS1Formulation

iTrader: (13)

Both of my factory plastic quick connects cracked and leaked on my '06 2500 HD. I'd look there regardless, they are a well known failure point on these trucks.

LS1 TJ

Back in the day I worked as line tech at Chev dealership. When we were looking for coolant leaks into the engine we would warm up the engine with the radiator cap off. Then pressurize the radiator with pump type pressure tester and then leave it sit over night. In the morning we would start pulling spark plugs to see if any of them was wet.
Oreilly's has a loan program for the pressure tester.