We are trying to locate where to check the transmission oil on this lift and fill hole. The forklift will not go into forward or reverse.

Shifter switches are ok as they are supplying good voltages to the spool valves on the transmission! So I suspect possible low oil level. The only port I see on this transmission is the one with the breather cap, we see no other plug or dipstick on the transmission! Would appreciate any help or pictures or drawings! Thanks