I mean its a dumb question but is there any true way to find out? I check my fluids in parking spot and its differernt then another. How do you know if your parked on flat ground?

 

A level?

 

get a pice of wood as long as your wheel base, put it where you'd park the car, and put a level on it, if it's level, it'll read level. Do the same for left to right, but really unless it's a big hill you should be alright.

 

most garage floors are level right?

 

I know for a fact that when something is spilled in my garage, it flows towards the door, so I'd say mine at least, is not level.

 

Grab a glass of water (don't use beer or any other beverage (for obvious reasons) and pour some on the spot in question.
If it's a paved surface, the water will start flowing downhill immediately if there's a slope, if it puddles; you're level.
On dirt, much the same thing but you'll have to observe it quicker....
Then again, I don't recommend jacking a car up on dirt under any circumstances. I lost a good friend when a car on jack stands came down on him (crushed his chest)...

P

 

ar...you can pour mercury on the floor or...put a tiny marble and see which way it rolls

 

its really not that serious. for checking fluids you can just eyeball it.

 

quoted from 2+2=5

"ar...you can pour mercury on the floor or...put a tiny marble and see which way it rolls"

.... and have your garage declared a SuperFund Site, thereby suffering several years of the EPA trudging thru your yard