1948 and earlier cars and trucks (at least back to 1937) used 4" rims with 6.00x16" tires.
And, the 6.50x16" car/truck tire (if available that year) was mounted on a 4.5" rim.
In 1949, cars changed to 5-bolt 15" wheels.
In 1949, 4" rim width wheels were used on Chevrolet trucks with 6.00x16" tires.
And, the 6.50x16" truck tire was mounted on a 4.5" rim.
I do not have my 1950 books with me.
From 1951 through at least 1955-1st series, 4.5" rim width wheels were used with 6.00 and 6.50 x 16" truck tires.
This information came from
model-year Specification manuals and
Owners's Manuals on Keith Hardy's website.
