All Toyota trucks have an information plate on the firewall or driverside door jam. The plate should be riveted seems your truck is an 83 newer models sometimes have a sticker. tag should read something like this ( CT/TR/A/TM 147 HR11 F302 A43D )
The 147 is the color code, HR11 is the trim code, F302 is the axle code and A43d is the transmision code.
Chart: for axle code
(CODE) GEAR DIA.(CODE) GEAR RATIO (CODE) GEAR RATIO #PINION
(F)- 7.5" (01) 3.30 (14) 4.87 (2) 2
(G)- 8" (02) 3.36 (25) 4.56 (3) 2
(H)- 9" (03) 3.54 (28) 4.30 (4) 4
(J)- 9.25" (04) 3.56 (29) 4.10 (5) 4
(K)- 9.50" (05) 3.70 (30) 3.73
(L)- 10.5" (06) 3.90 (37) 3.58
SO THE AXLE FOR THE TAG ABOVE GOING OF THE CHART F302 WOULD BE 7.5 GEAR DIA. AND 3.73 GEAR RATIO WITH TWO PINIONS MEANING 4WD. HOPE THE CHART HELPS OUT.