You can download a free owner's manual for it here:
https://www.ntractorclub.com/manuals/tractors/Ford 4000 Owners Manual.pdf
Here's how to decode the model#:
View attachment 782512
First number (1 digit)
2**** - 134 ci gasoline or 144 ci diesel engine
4**** - 172 ci gas, LP-gas or 172 ci diesel engine
Second number (1 digit)
*0*** - Industrial models produced prior to 1963
*1*** - Industrial and agricultural models produced after 1963
Third number (2 digits)
**10 * - Row crop
**11 * - Offset
**20 * - Utility-type w/adjustable front axle
**21 * - Orchard type w/ non-adjustable front axle
**30 * - Utility-type tractor w/non-adjustable front axle (light industrial)
**31 * - Low center of gravity (LCG tractor)
**40 * - Heavy duty industrial tractor w/sub frame
**41 * - Heavy duty industrial tractor w/sub frame & cast grille
Last number (1 digit)
*1**0 - Four-speed w/o PTO
*0**1 - Four-speed w/o PTO or hydraulics
*1**1 - Four-speed w/PTO
*0**2 - Four-speed w/hydraulics, w/o PTO
*1**2 - Five-speed w/live PTO
*0**3 - Four-speed w/hydraulics and PTO
*0**4 - Select-O-Speed w/o hydraulics or PTO
*1**4 - Select-O-Speed w/o PTO
*0**5 - Select-O-Speed w/hydraulics and single-speed (540 rpm) PTO
*0**6 - Select-O-Speed w/hydraulics, 540 and 1000 rpm PTO and ground-speed PTO
*1**6 - Select-O-Speed w/two-speed (540 and 1000 rpm) independent PTO
*1**7 - Select-O-Speed w/540 and 1000 rpm independent PTO and ground-speed PTO
*0**9 - Five-speed w/live PTO
Suffixes
-1 - Tricycle with single front wheel
-4 - High clearance with wide front
-L - LP gas engine
-D - Diesel engine
Thousand Series tractor serial numbers -
1962 Serial number 1001 - 11947
1963 Serial number 11948 - 38930
1964 Serial number 38931 - up
Part number identifiers cast into 134 and 172 engine blocks (lower right side)
EAE 6015 - 134 1953-1957
EAF 6015 - 172 1953-1957
310905 - 134 1958-1959
310609 - 172 1958-1959
B9NN-6015C - 134 late 1959 early 1960
B9NN-6015A - 144D late 1959 early 1960
B9NN6015J - 172 late 1959 early 1960
B9NN6015B - 172D late 1959 early 1960
C0NN-6015G - 134 sleeveless late 1962-1964
C0NN-6015H - 144D late 1960-1964
C0NN-6015C - 172D-G late 1960-1964
C0NN-6015J - 172 late 1960-1964