creamy sludge under cap

data: 09 trd off road, 4.0L. has about 5k miles on it.

i changed the oil in my truck for the first time last week. everything was ok and normal. i put in mobil 1 full synthetic and a mobil 1 filter.

i checked the oil level a few days later to make sure it was still ok and i also opened the oil fill cap and found a light beige color, creamy sludge under the cap and lined in the oil fill tube. i was told it was just condensation, so i cleaned it...but it came back. what is going on? why does it do this all of a sudden after i changed my oil? i drive 25 minutes to work (not what i consider a short trip) and it's been below freezing for several weeks before i changed the oil and no sludge. now all of a sudden immediately after i changed the oil...sludge? coincidence?

thanks,
adam

 

^^^Damn, beat me to it.

 

a combination of the cold outside temperature and constant higher underhood temps create condensation. h2o mixed with oil makes this creamy sludgy stuff under the cap. It is very common on todays vehicles. It was the same way for my dodge ram with the HEMI. It used to be a tell tale sign of a blown head gasket on older vehicles. Dont worry about it, its not hurting anything unless you see milky oil on your dip stick.

 

This has been discussed a lot lately. I use mobile one as well and I get the same gunk in the winter. I have 500 miles since my last oil change and once again there is gunk is in the cap and oil tube. I actually removed the oil tube today and cleaned it out. I'm going to try to warm up my truck longer in the morning since I only have a 7 mile drive to work. Long story short, I wouldn't worry about it. Atleast for me it's goes away when it warms up outside.

 

Read a couple threads on this earlier today and checked mine for kicks and giggles this afternoon; clean as a new whistle w/ a tad over 2k on the truck...I do let mine warm up on below freezing mornings, of which we've had plenty of this year, short ride to the office; perhaps I sat on a horseshoe?

 

It's normal for these trucks to have the sludge build up under the cap, the oil filler neck that the cap attaches to is quite long and it doesn't quite warm up at the end compared to the rest of the engine after short drives, causing the condensation. (Especially in the Winter).

 

ok. wish it wouldn't happen. but its nice to know nothing's wrong.

 

what type of oil do you use?

 

Same thing with mine.. Also happens in the Wifffs RAV 4..

 

mmm creammmyy