Why do US car brands end in a consonant like Chevrolet ("t"), Buick ("ck"), Cadillac ("c"), Ford ("d"), Jeep?

("p"), Dodge ("dge"), whereas Japanese / Korean car brands all end in a vowel like Toyota ("ta"), Honda ("da"), Nissan ("ssan"), Subaru ("ru"), Hyundai ("dai"), Kia ("a")? Why is this?