Without Googling, do you know what joke has the following punchline:
they both come in gallons!
Just answer yes or no. I’ll provide the actual joke once this thread reaches a decent size.
I’m curious because nobody I know in real life seems to have heard of this joke and searching for it reveals only a scant few references which leads me to wonder if it could be a new joke.
Yes. I’ve known that one since the late sixties, but haven’t heard it lately.
Yes.
Yes.
Yes.
Yes, I believe so.
Yes. Or at least I THINK I do… Obviously I won’t be sure until you post your version of the joke 
ETA: Oops, misread the instructions.
But yes.
Yup.
Curious, everyone seems to have heard of it and yet I can’t find more than 100 hits for it on Google.
The joke, at least as I’ve heard it goes:
How is elephant & milk the same?
Sure.
Similar one is Why does Dr. Pepper come in bottles?
Because his wife is dead!
Yes, but I’ve always heard it as quarts.
Nope, never heard it.
I had never heard it.
Never heard it, but I guessed it.
Never heard of it, but I guessed it was probably dirty.
Nope, but was able to guess from which direction the punchline would come.
Nope. Not exactly the most amazing punchline I’ve ever heard, though–I wouldn’t be surprised to find it’s ancient & just fell off the popular radar before the 'net got a full head of steam.
yes
Yep. Although I think “quarts” is the version I’m familiar with. Google seems to have plenty of references to this joke.
Don’t know if I still need to spoiler this or not, since it hints at the punchline by naming the animal involved:
edit: I’ve also usually heard this as one of many jokes in rapid-fire succession that involve elephants. Elephant jokes.
edit2: Heh. That Wikipedia reference even contains the OP’s joke.