My Scion buzz bomb has 4.31 final drive and .82 5th spd ratio. 5th seems about avg among compact cars but 3k rpm at 60mph kinda bites. I see the newer corollas has 6 spd with a .39 ratio. 61% OD? And the toyo has a 3.91 final drive also. Is that 6th gear only for hwy cruising?
Reviews say 5th gear max speed is 125mph. And 6 th gear max is 118. Motor lacks torque to move car faster in 6th gear?
Yep, 6th is there for cruising at 70, max mpgs. I think you’ll find that many cars with 6+ gears reach top speed in a lower gear.
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Newer CAFE demands mean the auto manufacturers have to find ways to meet them. Ten speed automatics are everywhere these days when CVTs aren’t used.
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IMO, that’s the definition of an overdrive gear.
Top non-overdrive gear ideally should let engine just reach peak HP RPM at top speed.
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No idea of Corolla’s gear ratios, but my truck has 4.11 diff & high gear is one to one. If I had a choice I’d prefer a little lower than 4.11 for the diff. And its a rugged-use 4WD truck. So I can why your sporty Scion with 4.31/0.82 5th might cause a little too much rpm rev’ing. I guess it depends on the engine torque vs rpm curve though.
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I assume truck has 30” tires? Vs the scions 24” tires. Truck is still probably 2500 rpm at 60mph
101 ft/lbs @ 4200rpm. Which is 72mph. Approx.
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Yes as circuitsmith and Wikipedia says. Transmissions are traditionally set for maximum performance and speed, with drive being for top speed. Over drive is added for economy and engine life. It started in the 70s with the fuel crisis.
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15 inch rims. Not sure what the truck’s actual tire diameter is. Mich LTX tires. No dash rpm gauge, but engine sounds to be rev’ing a little beyond comfort at 65-70 mph.
I assumed you have OD trans but might not. You might not even use od when towing. Most full size trucks have 28”-30” OD tires. So, I’m only making guesses. maybe you have a 74 dodge D200 logging truck
Really? My 1949 convertible had overdrive.
My first car a 1950 ford had overdrive.