It's pronounced willies..

From the comic strip "Shoe":
Editor "I need you to cover that story at the morgue"
Shoe "My car is in the shop"
Editor "Take that old Jeep out back, like you did last time"
Shoe "How come every time I have to go to the morgue I get the Willys?"

That's right, it's what W brings,
John Willys praises, the US sings;
from plain old cars to the almighty Jeep,
we owe him more than a peep.
 
It's an old brand, back to nineteen-oh-six,
some folks still drive them, just for kicks;
the '41's were a hot-rodders dream,
put in an Olds engine, and let 'er scream!


1935 Model 77 Willys



1949 Willys Jeepster



1954 Willys Aero



Here's a '41 that's done over