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My car has the E351 transmission and I was comparing the gear ratios to the U250E automatic that the current I4 Camrys use.

I am curious why the gear ratios on my manaual are all shorter than those on the automatic. For any given speed, the engine on a vehicle equipped with an E351 transmission will be spinning faster compared to a vehicle with an U250E.

But somehow, the city mileage on the two vehicles are supposed to be the same, per the sticker, but the manual has a 1MPG higher highway rating despite the shorter gear ratio.

What is going on here? I thought that since a manual transmission is lighter and more efficient than an automatic that it could have taller gear ratios and better fuel economy. The E351 weighs about 45 kg and the U250E weighs about 93 kg so the car would be somewhat lighter also...

BTW, what does counter gear ratio included mean?
 

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Apologies for resurrecting an old thread, but this came up while searching for info on the E351 and I was wondering the same thing as the OP. To me it seems bizarre that my 95 Camry MT 5sfe doing 100 km/h (60mph) was revving at approx 2800rpm while my newer 2004 Camry with the 2azfe MT is revving at the same rpm in 5th at the same speed. We also have The same I4 Camry in an auto and it revs significantly lower than this at the same speed. What was the reasoning for this by Toyota? I don't like it at all.

Over a long trip or the life of the car the manual transmission version has completed many thousands more rpm to achieve the same distance at the same speed! Surely this can only mean more engine wear? Maybe the E351 was used in heavier vehicles like the RAV4 and this was Toyotas blanket approach. Anyway the gears are very short and it seems odd!
 

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Cressida nut
91 Pickup (Hilux)2wd
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It's called marketing (aka cheating the numbers). Changing the gear ratios like that is the main way automatics have "advanced" to become more efficient than manuals. Look at the new Miata: same MPGs, autos geared 10% taller in the top gears. Yes the larger number of gears helps but that's also more parts to move, more lube required, more engineering and programming.

As for engine wear, very little wear happens from low load-medium RPM operation. A few cold starts will put far more wear on an engine than many hours operation at 2200 rpm instead of 2000 rpm on the highway.
 
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