Do I have the wrong dipstick?

New (to me) 2017 Prius Prime owner.

I have put about 6,000 miles on the car, and during this time the dipstick never changed in level, whether hot or cold. It’s up to the dot where Toyota marks the “normal” Full level of the crankcase, so I thought that’s perfect.

Recently I had some cold start rattling that was louder than what I felt comfortable with, so I checked the dipstick and it was still Full. Put a half quart of 0W-20 and checked after wiping off with a rag, no change. Put the rest of the quart in, still no change. The dipstick reads Full.

Now you must be thinking, car isn’t level, hot or cold, nope. Car sits in a level garage (a stick shift wouldn’t even roll when out of gear and no parking brake) and I have checked it in 32F and 85F weather.

But now my rattle noise is gone. So was I a quart low? Is there a chance someone put the wrong dipstick in my car, and if so, shouldn’t it be way over full if it truly was the wrong one? Or am I actually a quart over, and about to blow the seals on the engine?

First used car of many that has decided to throw me for a loop on the oil level!

 

To add to this thread, I let the car sit overnight (neither on a charger or been running for 8+ hours) and checked the oil, still at the "Full" mark. After doing some searching, however, I noticed that the dipstick I should have doesn't seem to have a mark at the "Full" level, which I've marked up on the photo attached.

This was just from a quick Google search showing the dipstick I should have (1530137010):

https://parts.toyotaofnashua.com/oem-parts/toyota-2008-2024-toyota-engine-oil-dipstick-1530137010

Can anyone confirm/deny that their 2017+ 4th Gen Prius Prime dipstick has the mark where the ? annotation is on the attached photo?

I'm now wondering if I was very low on oil (3 quarts or less in crankcase) or if I am now way over full. If it weren't for a slight injury I'm recovering from, I'd jack up the car and drain out all the oil just to be sure.

 

Here are photos of the dipstick, after being wiped off with a clean rag. I just drove 30 minutes so not all the oil has had a chance to drain back into the wet sump.

Also, I just noticed that if you flip the dipstick over, it actually reads way high - something I’ve not seen before.

For comparison, attached is the dipstick for my track car (2009 Corvette LS3), where GM says to overfill the oil by 1 quart (it clearly shows overfilled, and the distance between the middle and top dot is 1/2 quart). This dipstick shows the same thing regardless of orientation.

With the Prius, both sides are not equal to the top dot - am I way over on the Prius, or way under?

Photos: 1. Prius Prime dipstick pulled straight out, 2. Prius dipstick flipped over
3. GM LS3 with known 1 quart overfill (per manual), 4. Cub Cadet 243cc dipstick

 

Here is another reading back to back showing it right side up and flipped over. Which is correct, the first or flipped orientation?

 

I made some markups based on what I am seeing, in both cases (flipped vs, not flipped) the dipstick leaves open to interpretation which reading is the actual reading.

Wiping off the dipstick with a rag doesn't seem to correct this, I always get two "spots" where the reading could be assumed to be Full.

This is the forward-facing orientation:

Then after flipping the dipstick, we get this:


Really hope I didn't run this engine low, it's my baby, and if it was burning oil I feel like an idiot & should've just drained the oil out to begin with. Then I'd know 100% what's in the crankcase.

 

Thank you, @notspam3!

I will check the spark plugs when I have a day off. Let the car sit overnight and I’m back to the “It’s Full” on one side and over on the other. Maybe I really was a quart low and should have been flipping the dipstick over the whole time?

This story from Reddit sounds just like mine, and that owner has either low oil when reading one side vs Full on the other.

 

Thank you, it looks like I’ve actually been a quart low as I tried your method for the first time. It still left oil streaks, but I can clearly see its now at the Full mark (flipping it over reads way high still) so I guess the whole time I was low, just like the Reddit post I referenced above.

Hopefully no engine damage was done, and my cold start rattle seems to be gone for now. I’ll still check the plugs when I’m able to, it’s a 4 cylinder (a lot easier than Camaros and Vettes where the last 2 plugs nearly require wiper arm removal, lol).

 

That’s the issue, I was always at the “B” mark until I tried what @Mendel Leisk had suggested.

The whole time I saw “Full” then realized it was just residue from the tube. Basically the true level was likely close to “A” but the smears kept it right at “B” which was confusing.

Luckily nothing seems to have happened, but only time will tell.