Mystery Leak?

I have a 2001 Tacoma Prerunner and noticed this odd leak the other day but can't place where it's coming from

It's on the passenger side just below the door frames

I've checked coolant, brake, transmission fluid...all seem ok

I've added a picture of a couple drops against a white backdrop just in case it gives any help

I took it to a mechanic nearby and when he looked under said everything looked dry around the tires, the rack was dry...

Any thoughts?

 

Those pictures show three different spots all down the passenger side undercarriage

 

Yeah that amount of fluid is concerning to not find a source of the leak..doubtful you drove thru a puddle of hydraulic fluid or something..not much color to the fluid but it does look to be Petroleum based.. sometimes a quick smell test helps identify mystery fluid as does a finger rub between 2 fingers...is it oily, tacky etc..does it smell burnt etc.. you didn't mention power steering pump..you did mention the rack as being okay..at 1st I'd say brake fluid because of the location but your mechanic checked already..so how about your AC compressor..does your AC work as it should ? It's really strange a mechanic couldn't identify the fluid..you could always take it elsewhere to get a free estimate on repairs needed and they may tell you what's going on..

 

What does it feel like or smell like? Anything familiar?

 

That’s my thought, especially if none of the fluids are low

 

Thanks for all the suggestions!

It does feel "oily" and has what I can only describe as an "automotive" smell

The A/C may be something as it blows cold but then warm - but that's been happening for a couple years now.

I actually found the back passenger floorboard was soaked with oil. I had a jug in the back so am assuming maybe it just spilled

Which would be in this case most ideal...i'm going to try to sop up the oil and then degrease the oil spots underneath one more time and see if that was it - or I need to look at A/C

 

I'm betting it was oil you spilled in the back floorboard.

 

Check for a bottle in the back,could be leaking....