Sorry for the long post...

Was getting ready to make a 300 mile trip... checked the oil and it was about 1/3 quart above full mark. Only have 1000 miles on this oil change. And only 5000 on the blower install. Truck is at 85000 miles. It's not foamy or separated like there is water in there. But not a strong smell of fuel.

I decided to drain all the oil out and it seemed fine until the end... black sludge came out! (Has never been thick or black before) I poured another qt. thru to try to flush it out of the pan. It's too thick to come out. I shot some dereaser up the drain plug to try to thin out the sludge and get it all out. Mostly successful.

I think i am pushing some fuel into the crankcase and its mixing with oil and cleaning the hell out of the block, hince all the crap in the pan. Just want to know everyone's thoughts of this, and what i should do next. Thanks -JOE

 

How long have you had the truck? Do you know what oil was always ran in it? Were the oil changes always on a regular basis? Is there thick sludge under the valve cover? You should be able to check through the filler.

 

Bought the truck with 55,000 miles. Was super clean in and out (well maintained) Never had any issues with dirty oil etc. I've had the truck for a little over two years and am extremely particular about my vehicles. Oil changes at 2500-3000 using Castrol 5w30. Using Wix filters. Valve covers have always been clean. i imagine there is a layer of grime throughout the engine and now it's going to be spotless inside.

 

have u been adding coolant? if so might be leaking coolant out of the cylinder heads due to poorest heads. Pull the VC's and psi test the coolant system and check for coolant leaking out of the heads. close to the rocker arms. will c a clean spot were it's leaking. light check. done 2-3 sets a week for this problem for the past 6 months .( coolant leak, but no visible leaks, and pull covers and find the heads leaking) some thing to think about.

 

Well after my oil change i marked the overflow jug. Just went to work and back today, nice and easy... only 15 miles. Now the oil level is higher and the coolant is down. CRAP! Looks like i will be pulling valve covers tonight After it cools down i am going to pull the plugs and see what they look like too. What's the best way to pressurize the coolant system? Thanks.

 

With a coolant pressure tester...if you don't have one or want to buy one, you can probly loan one from a local parts house like autozone. See what pressure your cap is rated at, and pressurize it to a pound or 2 over the cap to test the system for leaks. You should be able to test the cap as well with an adapter that is part of the tester kit. It takes likes 5 min to test.

 

You are the BEST! Seriously! That was exactly what was happening Pulled drivers valve cover and pressurized to 15 psi. Could see coolant drops forming on upper center head bolt. Glad i found what the issue is. Now, should i change both heads or just the one (pass side looks ok) Dealer cost from Gm is like $263.21. Head gaskets? Good ol felpros, or what? Thanks again for all the help so far.

 

For what the dealer charges for one head, you could probably pick up a decent set of used 317's. They would drop your compression to about 8.5:1 and allow you to crank up that Procharger. With the right tune and probably some 60's (and/or Meth) you could run 14-15lbs and add a ton of RWHP. If you have to pull the heads, you might as well make it faster.

Stock GM MLS heads gaskets are a proven winner for boosted applications. Remember to step up to the LQ9 head gasket if your going to try the 317's.

Rick