Time for an oil change but the oil looks new?

Regan, welcome to PC. The Prius is very light on it's oil use particularly if used around town, less so if used on the freeway.
The oil change interval in the US (I assume that's where you are as you do not give this information in your avatar) is 5000 miles for the gen2 Prius. In the UK and Europe the same car is given an oil change interval of 10,000 miles or 1 year using synthetic oil, and even at this millage it comes out clean with very little discoloration.
The gen3 Prius oil change was extended from 5000 miles to 10,000 miles about a year or so ago in the US, and the Prius C that uses the same basic engine as your gen2 Prius also has the 10,000 mile change interval again using synthetic oil.
So basically what I am saying is if you use synthetic oil 10,000 miles between oil changes is fine, if you use dino oil keep to 5000 miles.
The service records for the car may show what oil was used last time.

John (Britprius)

 

It is very common on the Prius. The oil in my 01 is still brown when I change it at 5000 mi intervals but I still do it. This is after 122,+++ miles. I've never seen anything like it before.

 

I'm told that 1 year is the limit on oil changes regardless of miles driven. I only have about 2500 miles on the car this year. What happens with aged but low use oil?

 

I use 0w20 in my 2008 Prius now very close to 100,000 miles and no discernable oil use between changes at 10,000 miles, and as your finding still looks good.

John (Britprius)

 

I think the problem is with low usage possible water condensation in the oil. In this circumstance it is probably not worth the extra expense of using synthetic oil although there may be extra protection from synthetic against cold oil sludging where water contamination exists. And yes as I pointed out in my post the recommendation is for a maximum of 1 year.

John (Britprius)

 

I agree its about condensation. In Hawaii, this should not be an issue because of the temperate climate. I would run the oil for 5k regardless of age. I'm not sure what the shelf life on oil is but, I'm sure its longer than 1 year.

 

I would be happy to use 5 year old oil out of a sealed can. The one fluid I am very fussy about is brake fluid. I will not let the dealer top up my fluid for three reasons. They will use a can that probably has been open for weeks. Unless there is a leak the fluid should not need topping up, and in that case the leak needs to be found first. The fewer times the fluid container is open the less the chance of moisture or dirt entering the brake system.

John (Britprius)

 

I have always wondered how a brake fluid container which has been opened but resealed with the cap is worse than the vehicle's brake fluid reservoir which just has a rubber lid which snaps on to the top of the brake fluid reservoir, and subjected to repeated heat/cool cycles.

 

Looking back at my last oil change, it was after 10 months and 8000 miles. The used oil analysis came back OK. No water, TBN=3.7.

As for OP's original comment on the look of the oil, my experience is quite different. In my case it only takes a few days for the oil to go from almost colorless (new) to brown/black (old). I have always thought that's actually a good sign showing the oil is doing what it is supposed to do: carrying away dirt.