why do manual trans cars rev higher?

[Erin]

1995 corolla, manual. Doing 65 mph, the RPM sits about 2750 when in 5th gear (the highest). Clutch does not slip.
In any 4 speed automatic I have owned, the RPM would be closer to maybe 2300 when in OD and the converter locked at 65.

I searched around a bit and it seems these are pretty typical except some manual trans owners report even higher RPM’s in some cases (like 3,000 RPM at 60 MPH) So maybe mine is doing better than “normal”.

Point is, why would cars be geared in such a manner that the top gear for a manual would rev the engine higher than top gear (plus converter lock-up) for an automatic? A 5 speed and OD auto both have 5 “gears” (if we wanted to count the converter clutch which only helps reduce about 200 RPM anyways in some cases)

Is it perhaps to keep the ride smoother at higher speeds in a manual since the trans and clutch are not absorbing any of the engine’s roughness the way an automatic and heavy torque converter might?
Also to be fair – for the same model year and make of car, would this higher RPM situation still be the same?

Just curious why the difference.

Topic

[Nicholas Clark]

Pretty much all vehicles with two different transmission choices also come with different final drive ratios that come coupled with the transmission. Usually manual transmission vehicles have a numerically higher final drive ratio to make starting with the clutch easier and it makes the stick shift car more fun because it will accelerate faster. This is at the expense of highway RPM being higher. Look up final drive ratio on Google or Wikipedia and you will get a better explanation.

[Author]

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