I have an '04 3.7L with 62,000 miles. I've changed the oil pretty religiously every 3,000 miles since I bought it new, and while I take some longer trips with it now and then, it's mostly around town for about a 5 mile radius.

I've noticed in the past a small amount of foam under the oil filler cap, and read it was a sign I wasn't letting it warm up enough before driving, so for the past couple of years I've been making sure to give it plenty of time to warm up (especially in our Ohio winters).

I'm going to change the oil today though, and saw there's some light surface rust on the oil dip stick, and little sand (?) type granulars on the bottom half of the dip stick. There's also still a bit of foam under the cap (like 3/4 of a dime in size?).

Any idea what's up with this?

Coolant levels look fine, engine sounds fine, temp gauge never shows anything abnormal. Could it be something silly like the o-ring at the top of the dip stick, or something serious?

Thanks!

 

It needs some good road time. Like at least an hour at a time at least once a month.

 

The static warm-ups aren't helping at all. It'll warm up faster driving than sitting. There certainly should not be any "foam" inside the filler cap. Are you sure there isn't too much oil in it?

 

I have heard a lot of 3.7 guys talk about the foam on the oil cap and had the same thing in my 3.7 Dakota from what I have read its normal and the only thing dodge did to stop people from asking about it is put a baffle in the oil fill tube