Originally Posted by Jekerrville
FoMoCo DEF is designed your your FORD. Pays your money, takes your chances.
Unfortunately, Airstream Interstates aren't Fords, and Mercedes Benz charges a bloody fortune for DEF imported from Germany and sold by the liter, so getting it elsewhere is always
As long as the DEF meets ISO 22241, it's all exactly
the same stuff no matter who
makes it or where it's made or what brand name is on the bottle. The ISO is a very precise chemical specification. Which is one reason why I don't buy it at a truck stop pump despite the convenience, because the pump doesn't list an ISO specification for the DEF being pumped.