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The speedometer reading is adjustable via the various drive gears fitted at the transmission. Depending on which final gear ratio (differential gears) are fitted, the speedometer gears are changed to keep the speedometer accurate.
Contents |
Overview
Stock 1200 Speedometer gear ratio:
pinion teeth/worm teeth on trans output shaft * 17/5 (3.90 diff) * 18/5 (4.11 diff) for Wagon or Ute
Pinion | Pinion assembled into Sleeve
To adjust the speedometer for different diameter tires, change the transmission cable pinion cog.
* If speedo reads too fast, fit a bigger cog * If speedo reads too slow, fit a smaller cog
Given that stock is a 17 tooth pinion, moving to one more or less tooth is about 6% change. So by changing the pinion you can only get it to ±3 mph accurate. For example, at 100 mph, within 3 mph. Or at the standard 50 mph rating, a reading between 1½ mph (48½ to 51½) is the best you can hope for. For finer tuning the speedometer itself needs calibration. Or you could fit different diameter rear tires.
EXAMPLE: If you are reading say 60 when you are really going 50 then the speedo cable needs to slow down by about 20% to read more accurately. If the speedo drive has a 17 tooth cog in it try to find a cog that reduces by 20%. 17 X .20 = 3.4 teeth... 17 + 3.4 = 20.4 teeth, the closest is a 20 tooth cog.| Teeth | % change | 50 mph reading |
| 16 | 106.25% | 53.1 |
| 17 | 100.00% | 50.0 |
| 18 | 94.44% | 47.2 |
| 19 | 89.47% | 44.7 |
Correction Table, increase Teeth by:
| Actual mph | Desired mph | Tooth |
| 40 | 50 | 3+ |
| 43 | 50 | 2+ |
| 47 | 50 | 1+ |
| 50 | 50 | 0+ |
Estimated Tire Correction Table (for 3.9 diff)
| Size | Diameter | Difference | Pinion | ~Error |
| 165/55R12 | 19.1 | 88% | 19T | 0% |
| 165/60R12 | 19.8 | 91% | 18T | -2% |
| 165/70R12 | 21.1 | 97% | 17T | 3% |
| 155/80R12 | 21.8 | 100% | 17T | 0% |
| 175/70R13 | 22.6 | 104% | 16T | 2% |
| 195/50R15 | 22.7 | 104% | 16T | 2% |
| 165/70R14 | 23.1 | 106% | 16T | 0% |
| 205/45R17 | 23.5 | 108% | 16T | -2% |
| 185/60R15 | 23.7 | 109% | 16T/15T | 3% |
| 205/40R18 | 24.5 | 112% | 15T | 0% |
Pinion & Sleeve assembled
Part Numbers
32702 Sleeve 32703 Pinion gear 32707 Sleeve Assembly (includes pinion)
Also see: Transmission Case Part Numbers
NOTE: while they are color-coded, order by part number, not by color. For example, 63-series and 56-series cogs (pinion gears) use different color coding.
They are easy to replace by removing the roll pin...use your original Cog Body (Sleeve).
32707-18000 2-bolt style
32707-H1000 Thread: M22 Fix bolt hole: 7mm I.D. (Pinion side): 9.3mm I.D. (Thread Side):10mm
32707-H1000 1-bolt style
56 & 60 Series
56-Series Transmission and 60-Series Transmission
PINION (32703) 32703-18001 PINION ASSY-SPEEDOMETER (15T) 32703-18000 PINION ASSY-SPEEDOMETER (16T) $10.55 USD 32703-15400 PINION SPEEDOMETER 17T [White] $17.02 USD 32703-H1000 PINION SPEEDOMETER 18T [Blue] $15.67 USD
15T
SLEEVE W/PINION ASS'Y (3702) 32702-15400 ASSY-PINION SPEEDOMETER 17T $17.02 USD 32702-H1000 ASSY-PINION SPEEDOMETER 18T (B120, 1975-1979) 32702-H1001 ASSY-PINION SPEEDOMETER 19T (B120, 1980 up)
38425-18000
Automatic Transmission
32703-P2616 PINION SPEEDOMETER 16T (auto) $23.22 USD 32703-P2617 PINION SPEEDOMETER 17T (auto) $12.78 USD 32703-P2618 PINION SPEEDOMETER 18T (auto) $23.43 USD 32703-P2619 PINION SPEEDOMETER 19T (auto) $12.78 USD 32703-P2620 PINION SPEEDOMETER 20T (auto) $12.83 USD 32703-P2621 PINION SPEEDOMETER 21T (auto) $21.12 USD 32702-P2719 ASSY-PINION SPEEDOMETER 19T (auto) $30.80 USD
63-Series
32703-N9016 PINION SPEEDOMETER 16T $13.28 USD 32703-N9017 PINION SPEEDOMETER 17T $12.42 USD 32703-N9018 PINION SPEEDOMETER 18T $12.42 USD 32703-N9019 PINION SPEEDOMETER 19T $11.80 USD
Application
56 & 60 Series
B110 with 3.90: 17T B110 with 4.11: 18T B210 with A13: 17T B210 with A13: 18T (optional Sedan) B210 with A14: 17T to 0376 B210 with A14: 16T from 0476 B310 with A12 North America: 17T B310 with A14/A15: 16T
FS5W63A
NOTE: 63 5-speed and 4-speed pinion gears have a different part numbers, so perhaps do not interchange.
32703-N9016 16T * JDM A10 F5 * USA B210 F5
32703-N9017 17T * USA S10 1977-1979 * USA D21 2WD F5 * USA GC22 1987-1989 Nissan Van [RS5W71C]
32703-N9018 18T * USA D21 F4 1988-1989 * USA D21 2WD F5 1986-1992 SELECT
32703-N9019 19T * USA D21 2WD F5 1986-1992 SELECT
Pinion or Assembly
Each drive gear (on the output shaft of the transmission) works with a variety of different pinion gears.
For the A-series gearboxes, there is only one size of drive gear, which works with 16-19 teeth pinions. The sleeves are all the same, so all you need is the gear (not the assembly).
Different transmission have different methods:
* Jeep - offset holder is rotated to various positions for each gear * GM TH350 - two drive gears, each works with a range of driven gears * Nissan 720: all have 6T drive gear * Nissan 56-series, 60: driven gear is machined on the shaft * Nissan 4W63, 71B, 71: replaceable gear
Ratio Adapter Box
