[Redc7]

When the Stingray gets the new 8 speed auto it might break 30 mpg

Corvette To Acheive 30 MPG With New Eight-Speed Transmission | GM Authority

 

[Bigdog]

2914 coupe non Z51 at 72 mph in 70 zone and 68 in 65 zone, plus 63 in 55 zone on 450+ mile trip got 31.4 mpg with a 50 mile best of 33.9. Who needs the constant up shifting/downshifting of two more gears. Not me plus more money for it I bet.

 

[RCjr]

If it really does a lot of hunting up and down thru gears just to get an extra couple of mpg, I wouldn't be interested. The mileage we already get is a bonus but not the reason we buy these cars. Guess we will just have to wait and see.


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[kp51]

I have got 30mpg on a couple long highway trips already at 70-75mph (base auto C7). I think a lot of manual guys never go into eco mode so they dont get a lot of V4 action, the auto cars are in V4 a lot, even lightly accelerating up some small grades.

FWIW I went from a '12 Ram 1500 4x4 with the 'old' 6 spped auto to a '13 with the new 8 speed auto (same model/options), the 8 speed even has active grille shutters that close for improved aerodynamics, average mpg is only like .1mpg better 50/50 hwy city. Highway mileage isnt a whole different either since its the same ratio in 8th as the 6 speed was in 6th. It does get rid of some acceleration dead spots though, like in the auto C7 if you floor it at 42mph and it doesnt shift down into first, takes a bit to wind up in 2nd. Plus if they can eek 5% more efficiency out of it thats a bonus, plus if its stronger for future horsepower increases.

I welcome the 8 speed, I dont think its really going to make a huge difference in anything but GM has to join the multi-speed trans wars so why not put one in a Corvette.

 

[Rotherd31]

My GF has a BMW 328i with the 8 speed auto. I have an X1 35i with the six speed auto. I really don't like her 8 speed. Damn thing is upshifting and hunting all the time. Not so with the 6 speed in my X1. My C-7 is an auto and I've already been between 29-31 MPG in Eco, when I can contain the 18 yr old inside me. A six speed auto suits me just fine. If I wanted more MPG I'd drive a Hugo!

 

[mjw930]

My GF has a BMW 328i with the 8 speed auto. I have an X1 35i with the six speed auto. I really don't like her 8 speed. Damn thing is upshifting and hunting all the time. Not so with the 6 speed in my X1. My C-7 is an auto and I've already been between 29-31 MPG in Eco, when I can contain the 18 yr old inside me. A six speed auto suits me just fine. If I wanted more MPG I'd drive a Hugo!

While your comparison has merit when implemented correctly the new 8 speeds out class the transmissions they replace by leaps and bounds. I can relate direct experience with the SRT transmissions in the Jeep SRT8. I had a 2012 with the Mercedes sourced NAG1 transmission and while not the most sophisticated it is and was considered a very good box. Enter the 2014's with the 8 speed ZF, the vehicle is transformed. On the track the quick shifts and closer gearing keeps the vehicle in the power band without upsetting the car when shifting, something that can't be said of the NAG1. Shifts are immediate and rev matching simply works. Around town the gear changes are virtually unnoticeable unless you are in sport or track mode. While I was perfectly happy with the 2012 I realized after 20 minutes in the 2014 that it was a markedly better vehicle. The same will be said of the C7 with the A8, mark my words.