condensation
 

my 06 hummer h3 is getting milky stuff on oil cap.has 80,000 miles runs great.not loosing coolant.not over heating.smooth idle.no smoke out exaust.no loss in power.anyone else have this problem? or any idea's?

driving short distances in cold temps can cause that.
Drive it for half an hour so it gets good and warm. Then see if it goes away

I tried that still getting it.

The only time i ever take the cap off is to change oil! don't know!

When oil is milky looking there is water present. Water is getting in somehow. I would drain all the oil and start over. Flush it out before adding new oil. Then see if it happens again.

Hey i was wondering if your hummer is still running and driving ok? My 08 h3 runs great and iant smoking or loosing any coolant but when i check the oil dipstick there is a milky substance all over it!!

https://cimg4.ibsrv.net/gimg/www.hum...c94abde55d.jpg

What do you mean its running out of time?

you need to drain your oil and see if coolant is mixing if so it needs to be remedied quickly if not boom! blown engine.

Years ago, circa 2013, the oil cap has a small amount of sludge buildup. I changed the oil and filter. Hasn't happened since. I change oil every 3-5K. Since then, I have replaced two Coil-on-plug packs and all of the spark plugs. Hope this helps?
My H3 is a 2006 with a VIN within the soft head issue.... haven't had a misfire or cyclinder 5 misfire in quite some time. But I don't drive it much.. currently has 100,500 miles. It has other issues but they're unrelated to this post.