The CJ-6 was simply a 20-inch (508 mm) longer-wheelbase (101 in, 1955-1971 - `04 in, 1972-1981) CJ-5. Introduced in 1955 as a 1956 model, the CJ-6 was never very popular in the United States. Most CJ6 models were sold to Sweden and South America. The U.S. Forest Service put a number of CJ-6 Jeeps in to use. American sales ended in 1975. Just 50,172 had been made when the series went out of production completely in 1981. Just as in the CJ-5, the V6 and V8 engine choices appeared in 1965 and 1972. Former President Ronald Reagan owned a CJ-6 and used it on his California Ranch.
The Military version, the M-170, actually entered production in 1953. It shares many of the features of the M38A1 (Military CJ-5), but had the passenger door opening extended back to the rear wheel well. Most were used as front-line field ambulances, able to carry 4 litters. A few were also used as radio units.