So I have a 1994 E-150 (Club Wagon) with a busted radiator. To replace it I need to buy a flare nut wrench to disconnect the transmission cooler lines from the radiator, but I have no idea what size wrench to get. I could get a set, but not even sure about if SAE or metric. Can anyone post the correct size of the radiator line nuts so I don't end up with a lot of paperweights please? Thanks.

 

Use an open end wrench to test fit.

 

That's too easy.

Or get a micrometer for six bucks at Harbor Freight. I don't think I'd trust an HF micrometer for precision machining, but it would be good enough for sizing nuts and bolts.