4.6L Sludging Oil

[tgrfly]

I'm at a loss here guys. Here for the last few oil changes my oil has been sludgy. It's not til I get to last bit of oil in the pan , but it shouldn't be there.

Took the truck to a shop the other day and had a hydrocarbon test done and it passed (thank goodness) meaning no cracked/leaky head gasket or cracked head. This was my main worry. What else could cause this? I'm at a complete loss.

Forgot to mention, the oil pressure is also good. I have a digital oil pressure gauge and it doesn't fluctuate during driving or at idle.

 

[Number4]

How many miles on engine?
How long between oil changes?
What oil and oil specs?
Oil hot when you drain it?
Oil color normal?
Any pics of said sludge?

 

[tgrfly]

How many miles on engine?
How long between oil changes?
What oil and oil specs?
Oil hot when you drain it?
Oil color normal?
Any pics of said sludge?

Typically 5k between changes on Valvoline MaxLife 10w-40. Using a Mobile 1 filter. Oil is typically at least warm when I drain it. Oil color doesn't seem to be off. Looks like used oil should. I don't have any pictures of the sludge.

I do have a milky substance in the filler cap and neck but that's it. It's not in the oil.

 

[tgrfly]

Any help on this?

 

[Joe in NY]

whoa, 10w-40?? Why so heavy? These motors are supposed to run a light oil at higher volume vs heavy oil at lower volume. The oil could be sticking around in places longer than usual and suck up moisture.

Do you take it for long drives to heat the oil up and boil the water out or is it short drives only?

 

[tgrfly]

whoa, 10w-40?? Why so heavy? These motors are supposed to run a light oil at higher volume vs heavy oil at lower volume. The oil could be sticking around in places longer than usual and suck up moisture.

Do you take it for long drives to heat the oil up and boil the water out or is it short drives only?

Typically 20min drives to and from work. That's about the most it gets driven. The occasional 45min to hour drive.

 

[Tyleryac]

You should be using 5w-30 just as the engine calls for.

 

[Joe in NY]

^^^ Wrong.

5w-20 is for V8. no big diff. But better for winter.