Checked the oil yesterday and noticed that where the dipstick has its first bend (6 inches or so from the bottom) a residue had collected. Dark red/brown in color. Seemed like baked on thin layer of oil, that I was able to scrape off. The oil looked fine. Any ideas? Never seen it before on any of my other vehicles. Engine runs fine.

2000 S70 GLT with 72,500 miles.
--
2004 XC90 T6, 2000 S70 GLT

I just bought my 2001 V70 off the internet and from New Jersey!
The car is great just as advertized. However, when I checked the oil before I drove it home(the car was transported to California) I noticed the dipstick had some rust on it and the tube appeared rusted as well.
I also surmised that since this was an east coast vehicle the moisture explanation sounds plausable. To remove the corrosion, I just flushed some engine oil down the tube, the filter will trap the rest.

Lots of FWD brick owners complain about deposits on their dipsticks in the winter. Do a search to read some.

I think that this is due to the dipstick tube being out front, staying cool in the winter and attracting condensation.

It is also quite difficult to clean the inside of this tube, although it is easy to clean the dipstick. When I cleaned the tube with narrow strips of rag wound around my dipstick, the condensation took quite a while to return, in my mind confirming my supposition.
--
96 855R, 95 855,854, 90 744 Ti - 343,000 Volvo miles put on 7 bricks

I am not sure how long this deposit has been on there as I purchased it in March and for some reason never noticed it before. I am usually pretty observant so I am not sure if it is fairly new or been there since I purchased it. After reading about a cracked engine block I think it got me paranoid and is probably the reason why I noticed it now. Oil looked "clean", or free of contaminants, like anti-freeze. It has been extremely hot and humid lately during the day and cool in the mornings.
--
2004 XC90 T6, 2000 S70 GLT