Running uphill in 6th gear == bad for oil?

[ueberooo]

I thought it was understood that the standard definition for efficiency is understood here. That is E_in/E_out = chemical energy of fuel / mechanical energy produced by engine (or P_in/P_out in terms of power)

This is basically what the brake specific fuel consumption BSFC tracks.

If you look in the chart posted by eljefino on page 1 of this thread you will see that maximum fuel efficiency does not sit at full throttle.

because it is such a splendid chart, here it is again:

Note, this is specific to a certain 4 cylinder engine. The data will vary from engine to engine, but given a similar 4 cylinder engine, it will be qualitatively very similar.

 

[gregoron]

My 2.slow 5 speed runs 70 mph at 3500 rpm going up a 5 mile stretch of highway rising from sea level to 900 ft. Yet, I'm only stepping less than 1/3 on the accelerator. The car is running really smooth and most cars can't keep up because they're most likely on top gear at 2,000 to 2,500 rpm. It's like the Jetta hit second wind despite its 2,500 rpm max torque rating. If I followed max efficiency and ran it at 80% WOT or at WOT I'd be flying and would face jail time if I got caught. I think that efficiency and practicality go hand in hand.