the 37 divided by 11 equals 3.36 may be a 1/2 ton? someone here will let you know. as far as I have found out the rear end ratios for a 1951 3/4 ton wich I just did a swap on from 4:57 to 4:11 are as follows - 5:14 or 4:57 or 4:11 and the hard to find 3:73 that came in some 67 to 72 big block automatic trans suburbans.
Look for a 3/4 ton with automatic trans up to a 1972. You can just remove the rear cover to see the numbers to tell what ratio it is without removeing the pig/pumpkin. Your 53 should be the same as my 51 if it is a 3 speed -10 bolt to houseing 8 bolt axel shafts. good luck Bill