2001 Tahoe 4.8l oil issue

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Odd question, but would a rig sitting for three years cause water/condensation build up in the crankcase?

My father in laws 01 Tahoe (4.8l, with 163k) that sat for three years, I got it fired up for him, he then took it to get the oil changed and cooling system checked at a local shop. They told him the crankcase was over full, with the oil being milky. They showed him a video of draining it, the oil looked light brown, but not that milky. Shop told him he probably needed a new engine. Note, my father in law told me he was having to put coolant in it every so often prior to parking it when he retired.

They changed the oil, topped off the coolant, and my father in law brought it home.

I recently bought it from him for $1500 intending to rework the engine. The rest of the rig is in awesome shape and it rides great. So I felt it was a fair price for potentially having to do engine work on it.

I drove it approximately 50 miles home, the temp was in the normal range of around 210, and the oil pressure never went lower than 40psi according to the stock dashboard gages. I checked the oil when I got it home, and it is clean and clear.

Debating if I should drop the pan to see what's going on.

Was wondering if anyone had experienced anything like this.
 

Scottydoggs

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sounds like it needs a head gasket. you can always do a compression test to see if they all match. if you find a low one thats the side with the bad head gasket. theres also tests that will let you know if theres exhaust in the cooling system.
 

OR VietVet

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Get the compression test done asap. Are you saying that in the 3 years it sat, no one started the engine? It just sat with no start and no movement? The kind of environment that it sat in can make a difference. That is why valuable vehicles that sit for long periods of time are typically in a temp and humidity controlled environment. The heads and rest may or may not be ok. Also, do a cooling system pressure test. If you do the compression test, and have a low cylinder(s), doubt it since you did not say it drove with a miss, make sure to do a wet test to see if is rings or valves causing low compression but again, I doubt it. I am assuming no CEL? Report back and when you do the compression test, replace the plugs and do the wires. I would also do the fuel filter. Please tell me you had fuel protection of some sort in the rig while sitting and if not I hope it has a full tank of top tier fuel in it now. What does the trans fluid look like?
 
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Get the compression test done asap. Are you saying that in the 3 years it sat, no one started the engine? It just sat with no start and no movement? The kind of environment that it sat in can make a difference. That is why valuable vehicles that sit for long periods of time are typically in a temp and humidity controlled environment. The heads and rest may or may not be ok. Also, do a cooling system pressure test. If you do the compression test, and have a low cylinder(s), doubt it since you did not say it drove with a miss, make sure to do a wet test to see if is rings or valves causing low compression but again, I doubt it. I am assuming no CEL? Report back and when you do the compression test, replace the plugs and do the wires. I would also do the fuel filter. Please tell me you had fuel protection of some sort in the rig while sitting and if not I hope it has a full tank of top tier fuel in it now. What does the trans fluid look like?
The Tahoe was out side parked in a driveway, in the normal summer/winter of the Seattle area.

Over the time it was parked, it may have been started once or twice, I am not 100% sure.

It was not planned to have been park the length of time it was, but life happens, so there were no long term storage measures taken for preserving the engine/transmission. I do know a few months before it was parked, the transmission had been serviced.

CEL? Not sure what you are asking on thar one.

Upon initial start up before taking it to the shop, it took three false starts with a new battery prior to staring running, with minimal smoking.

When I drove it home, it had good power, no misses, the transmission shifted fine. My wife who was following me told me there was no smoke, and while I was letting it warm up, I did nor smell any tell tale coolant in the exhaust.

I will be doing a compression test next weekend on both the cylinders and the cooling system.

Is there a casting number or Vin decoding trick to determine which heads I have?

Also there are no codes stored in the computer when I plugged in my code reader, no service engine light on. Part way home the ABS light and the Brake light indicator came on, but the Master Cylinder was full, so another gremlin to chase.
 

OR VietVet

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CEL=Check Engine Lights.

I would do a complete brake fluid flush asap. The brake system is vented and the fluid is hygroscopic and absorbs moisture in the air. May explain the ABS and brake light but needs anyway and could get lucky. Brakes feel ok though? The 3 false starts were likely because the fuel system bled off while parked and needed to re-prime itself. Pics of rig please.
 

rockola1971

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210 degrees is normal. I suspect combustion gases are entering your coolant system. Does engine warm up really fast? Cracked head or blown head gasket. Either way the heads are likely gonna need pulled. With only 163k on the Tahoe I would throw a set of reman heads if needed. Complete flush of engine oil with some kerosene. Compression test and cooling system pressure test will tell you whether the heads have to be pulled or not.
 
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