Checking oil with truck on or off

Newb question, but are you guys checking oil with the truck running or off? My truck never had issues I just put the 5.5 quarts in and checked once in a long while. However recently I had the notorious timing chain cover start leaking. I'm checking it more often and started second guessing myself checking it when the truck is off. Anyway seeing what you guys do, thanks!

 

Check it with your truck off and the engine cold. Once it's running oil is moved up into the head ofor the engine so this will give you a false reading and when the oil is warm it becomes thin and expands this will show higher on the dip stick

 

http://lmgtfy.com/?q=Do+I+check+engine+oil+with+the+car+being+on+or+off

 

Ok great thanks man. I checked it with the engine running and warm and it only showed about 1/4 inch up on dip stick and made me nervous. It's good when truck is off though

 

Ya check either first thing in the am or after work even let it sit for 20 min before checking. I've only seen certain pieces of machinery (diesels) have you check engine oil while warm and it will have 2 marks on the dip stick one for cold and one for war. Your transmission will be warm with the engine running

 

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