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The Micra's automatic is a conventional 4-speed with torque converter, but beyond that the owner's manual has precious little to say about it.

Here's what I can say about it:



  • Smooth upshifts: it's remarkably seamless under light to moderate acceleration.



  • As far as I can tell, it locks the torque converter in both 3rd and 4th gears ( a fuel-saving feature). In 1st and 2nd gears the engine will rev freely when you press the accelerator regardless of road speed, but in 3rd and 4th under light/moderate load, the torque converter locks and changes in engine RPM are tied directly to road speed, just like a manual transmission.



  • Upshifts/lockup under light to moderate acceleration happen at roughly:
    19, 35, 41 & 59 km/h .... (12, 22, 26, 37 mph) ... when the engine is warm.



  • The car's most efficient cruising speed on the level is just after the torque converter locks in 4th gear (at ~59 km/h). Once it locks, you can drift down as low as ~55 km/h before it unlocks again, provided you don't prod the accelerator and kick it out early.



  • Deceleration fuel cut-off: the car has pretty aggressive DFCO, another fuel-saving feature. When you lift off the accelerator in either 3rd & 4th gear, fuel injection stops. You're using zero fuel while the momentum of the car continues turning the engine through the transmission's connection to the drive wheels. The car will stay in fuel cut-off mode as it decelerates through a 4th to 3rd downshift. Once the torque converter unlocks in 3rd gear, RPM drops noticeably down to hover around 1200 and fuel injection resumes while you continue to decelerate.

    The small downside to aggressive DFCO is it can make for slightly herky-jerky driving if your throttle input is hovering right around the DFCO threshold.



  • Speed vs. RPM in top gear w/ locked torque converter...

    I'll graph this later...

    Speed (km/h, indicated) RPM (from OBD-II -- reads slightly lower than the dashboard tach)
    50 1662
    60 1450
    70 1687
    80 1925
    90 2150
    100 2425
    110 2662
    120 2972



  • Overdrive button: you can downshift from 4th and hold 3rd by switching overdrive OFF (for engine braking).



  • Shift lock release: if you have a dead battery, you can override the electronic shift lock (e.g. to get the trans into Neutral to push the car) by prying up the little cover, then pressing the shift lock button while shifting out of Park.


I'd still rather be driving a manual!

It's frustrating to be held captive at a higher engine RPM than needed. Plus, the manual Micra's shifter and clutch were light & pleasant enough to use that I wouldn't mind it at all even in city traffic. If I can't shift my own gears, give me a CVT that varies the gear ratio based on immediate conditions.

I understand Nissan's desire to cut costs (the official reason for no CVT), but two of its closest competitors are now using Nissan/JATCO-sourced CVT's for improved fuel economy (Spark & Mirage). So while Micra owners with the 4-speed automatics are saving a few dollars up front, they're spending more on fuel in the long run.

Many car reviewers would whine about a CVT. Let them whine! Most car buyers don't care what car reviewers whine about.