A4 cars, what is your highway milage with 2.73, 3.15 and 3.42
05-26-2013, 06:47 PM
#1
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A4 cars, what is your highway milage with 2.73, 3.15 and 3.42
Considering a gear swap and I'd like to maintain good economy at 75mph.
my 2.73 currently sees about 29-31 inst MPG on the highway on a straight/level stretch with the cruise engaged at this speed
Those of you with 3.15 and 3.42 gears, what do you guys see at 75?
my 2.73 currently sees about 29-31 inst MPG on the highway on a straight/level stretch with the cruise engaged at this speed
Those of you with 3.15 and 3.42 gears, what do you guys see at 75?
05-26-2013, 06:50 PM
#2
Race Director
I don't have an automatic but I get 30-31 mpg on the highway with my 3.42's at 75-80 mph. This was tested on a 3,000 mile trip to Arizona and back.
Last edited by Corvette_Ed; 05-26-2013 at 07:02 PM.
05-26-2013, 07:01 PM
#3
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I can't speak for 75 MPH, I haven't put the '03 on the freeway, later this summer. My over all mileage was 24+ with 2.73's in a '97 coupe, I'm getting almost 23 in the '03 Vert with 3.15's under almost the exact same conditions. I'd say I lost 1.5-2 mpg, totally worth it.
That said, the 3.15's really wake up an A4, better throttle response at all speeds and all gears. I think if I was actually swapping gears I'd go for the 3.42's.
That said, the 3.15's really wake up an A4, better throttle response at all speeds and all gears. I think if I was actually swapping gears I'd go for the 3.42's.
05-27-2013, 07:32 AM
#5
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St. Jude Donor '08
I can't speak for 75 MPH, I haven't put the '03 on the freeway, later this summer. My over all mileage was 24+ with 2.73's in a '97 coupe, I'm getting almost 23 in the '03 Vert with 3.15's under almost the exact same conditions. I'd say I lost 1.5-2 mpg, totally worth it.
That said, the 3.15's really wake up an A4, better throttle response at all speeds and all gears. I think if I was actually swapping gears I'd go for the 3.42's.
That said, the 3.15's really wake up an A4, better throttle response at all speeds and all gears. I think if I was actually swapping gears I'd go for the 3.42's.
I got around 27-28 mpg with the 3.15 hwy mileage, probably slightly less at 75mph. I get around 23-24 mpg with the 3.42's
05-27-2013, 09:59 AM
#8
Racer
I20, i35,traffic
I drive 48 miles a day in metroplex traffic, on i20 and i35 traffic which is wide open or crawling, i average 20-22 with a-4, 3.15. Last year on a road trip of 300 miles i got 27mpg, that's with some spirited driving. 
05-27-2013, 10:03 AM
#9
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I have the 3.15 gears in mine and I get about 26-27 mpg at 75 mph with cruise engaged.
05-27-2013, 10:08 AM
#10
Burning Brakes
I have a 2.73 in my 02 A4 coupe. I get about 29-30 mpg highway cruising. I get 17-18 in town in rush hour commuting. I appreciate the good mileage. I would like to swap in 3.15 gears; they seem to have little effect on mileage, but I would not go to a 3.42.
05-27-2013, 10:15 AM
#11
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That's what I'm thinking about now. A 15.4% increase in torque is worth a 1-1.5 MPG sacrifice.
05-27-2013, 10:22 AM
#12
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With the cruise set at 75 where legal, and many spots 80 going from Salt Lake City down to St. George we average between 28 and 29 miles per gallon. This is up and down many mountain passes. We have a 99 auto that came with 3.15's and we desired a bit more and went to 3.42's. Have been VERY pleased with the "slight" increase. My around town driving mileage seems to be affected by the change over the highway. STILL, worth it, in our opinion.
Last edited by robertlthomson; 05-27-2013 at 10:25 AM.
05-27-2013, 10:27 AM
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St. Jude Donor '12-'13-'14
With the cruise set at 75 where legal, and many spots 80 going from Salt Lake City down to St. George we average between 28 and 29 miles per gallon. This is up and down many mountain passes. We have a 99 auto that came with 3.15's and we desired a bit more and went to 3.42's. Have been VERY pleased with the "slight" increase.
It isn't worth the cost for such a little gain, If I ever do change gears it will be 3.90 so I can feel it...lol
05-27-2013, 10:40 AM
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I'd expect 25 at 75 mph with cruise set. I can stretch it to 28 if I work at it and play the throttle gently.
3.15 gearing.
3.15 gearing.
05-27-2013, 10:44 AM
#16
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24.8 MPG
Thanks,Matt
05-27-2013, 10:49 AM
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How come none of you are stating which TRANSMISSION gear you are in? With my 2:73 I get 32 mpg in D, and 31 in 3rd....with a helluva lot more torque and pull in 3rd!...whenever I start thinking about switching rear DIF gears, I just put it in 3rd on the highway and fuggettaboutit!
05-27-2013, 11:34 AM
#20
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How come none of you are stating which TRANSMISSION gear you are in? With my 2:73 I get 32 mpg in D, and 31 in 3rd....with a helluva lot more torque and pull in 3rd!...whenever I start thinking about switching rear DIF gears, I just put it in 3rd on the highway and fuggettaboutit!
the car wouldn't break the tires loose if I stomped on the gas from a stop.Now, when it automatically shifts into third at 85, sometimes the traction control light comes on from breaking loose - now I don't "stomp" but sort of squeeze the trigger
I wouldn't want to be driving around in 3rd unless I'm making a pass at the track or hunting on the street... that's why.