Advice on transmissions: 8-speed vs 6-speed (auto & manual)
 

I have been researching the A4 for quite some time, and have always had in mind, the 6sp manual. However, with the arrival of the new 8-speed Auto in the '11 models, the automatic option became a possible option.
My first choice would be the manual, but that would mean that my wife would never be able to drive the car, as is my current situation. I didn't think about the 6sp auto previously because I have a 90 mile commute (round-trip) for work, so fuel economy does play a role in choosing my next car.

According to Audi's website, the 8sp auto has a final drive ratio of 3.517, and the ratio of gear 8 is 0.37. That gives an effective gear ratio of 1.30. The Sport package comes with 245/40R18 = 784 revs/mile. So, according to my calculations in 8th gear:
@1000 RPM ==> 58.81mph
@1500 RPM ==> 88.22 mph
@2000 RPM ==> 117.62 mph
@2500 RPM ==> 147.03 mph
These speeds seem rather high for a 4cyl in which I have read the engine is lacking a bit in torque below 1500 RPM.

Similarly, the manual has a final drive ratio of 3.693, 6th gear ratio is 0.692. With same wheels, then in 6th gear:
@1000 RPM ==> 29.95 mph
@1500 RPM ==> 44.92 mph
@2000 RPM ==> 59.89 mph
@2500 RPM ==> 74.87 mph
These seem reasonable for a 4 cyl engine.

Those with the 8sp, what are you 60, 70, 75 mph cruising RPMs?

Also, how does the 8sp Auto compare to the previous 6 sp auto? I already know I would enjoy the manual, but if I want a car that my wife can drive, it means 'Auto.'

FYI, my A4 of choice would be a Premium Plus, with Sport Package, and B&O system...

Any feedback would be greatly appreciated...

(Apologies if someone has posted this before, I searched but did not find anything similar)

I absolutely love my 8 speed auto. It's the smoothest and fastest shifting auto I have ever driven. I cruise at about 75 mph and the engine is at about 2000 rpms. I find that the engine has plenty of torque for me. However with a loaded car dropping into 7th or 6th for a quick pass would be necessary. S-mode is wonderful and resolves all of my power needs. When im just driving around town or cruising on the freeway "drive" mode is sufficient for me and returns the best mpgs.

Ah, it looks like Audi's website has the Multritronic and Tiptronic Final Drive ratio's swapped.

With a 5.970 Final Drive on the 8sp auto, 2000RPM = 69.29mph, matches exactly what you said.

Thanks, I have that part figured out now.

For an unrelated datapoint, on my CVT, at 75mph, in standard drive mode, my RPMs are 1850 or so.

1900-2000 rpm @ 75 mph

it looks like the EPA bumped the rating from 27 mpg to 29 mpg on the highway with the 8spd auto. I don't know what the ratings are for the 6spd manual, but suspect they're similar.

I would have been in the same boat as you had they offered the 8 speed auto when I was ordering the car in the fall of 2009. That said the manual I got was listed at 22 city/30 hwy and I'm thrilled with the mileage I'm getting with it. Not sure about the RPM at 75mph. I'll check tonight. The manual is fun and makes the car. I sacrificed getting an Avant just for the manual and don't regret my decision.

That's a + in my book:D

Why would your wife never be able to drive the car if you went with the manual?

Because I'm sure he is in a similar situation as me. No matter how much she tries she never really felt comfortable driving manual. Having kids now the last thing I need is the wife to be in a panic driving around town with the kids in the car.