5.0's Only!! 3.31 v 3.73 :: A Gas Mileage Comparison
7/13/10, 10:04 AM
#1
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5.0's Only!! 3.31 v 3.73 :: A Gas Mileage Comparison
An interesting idea was brought up in a different thread, and I figured I'd go for it. Looking for manual 5.0's, with 3.31 or 3.73's, to report your gas mileage. Please include how it was achieved - percentage (rough estimate) of city vs. highway driving, lots of idle, etc.
With 3.73's:
Personally, on my first tank, I got a raging 17 MPG. This was due to attempting to vary my RPM's and engine load as much as possible, for a nice break in period.
Second tank, was around 19 MPG. A bit more highway mileage with this one. Note: I went through two tanks of gas in the first day of ownership, so. Ha.
Ever since, with a roughly 80:20 (Highway:City) split, I've been getting between 21-23 MPG. This is with me hotrodding it whenever I'm under a bridge, coming off several of my favorite stop lights in town, and several very, very nice kills on the local highway (This week: Pontiac G8 GT with full bolt ons, and a 2008 WRX STi with a turbo-back exhaust).
Really enjoying this car, and these gears. I had 3.31's in my 08 GT, with 4.10's sitting in a box still in my garage that were never installed. This 11 GT just absolutely rips.
With 3.73's:
Personally, on my first tank, I got a raging 17 MPG. This was due to attempting to vary my RPM's and engine load as much as possible, for a nice break in period.
Second tank, was around 19 MPG. A bit more highway mileage with this one. Note: I went through two tanks of gas in the first day of ownership, so. Ha.
Ever since, with a roughly 80:20 (Highway:City) split, I've been getting between 21-23 MPG. This is with me hotrodding it whenever I'm under a bridge, coming off several of my favorite stop lights in town, and several very, very nice kills on the local highway (This week: Pontiac G8 GT with full bolt ons, and a 2008 WRX STi with a turbo-back exhaust).
Really enjoying this car, and these gears. I had 3.31's in my 08 GT, with 4.10's sitting in a box still in my garage that were never installed. This 11 GT just absolutely rips.
7/13/10, 10:38 AM
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3.73s - 1400 Miles - 50/50 Highway/City
Got right at 18 last fill up with a hand calculation
Driving home from work last night I put it at 75mph for 5-7 min and kept it there via cruise control, road was fairly flat.
Got 21.4 MPG over that time period via the computer. Don't know how the EPA calculates highway @ 26MPG but I do not see myself getting near that unless I get some gains as everything breaks in in a couple thousand miles. Not that I expected that with 3.73s anyways... lol.
Curious to see what those with 3.31 5.0s get mileage wise as well.
Got right at 18 last fill up with a hand calculation
Driving home from work last night I put it at 75mph for 5-7 min and kept it there via cruise control, road was fairly flat.
Got 21.4 MPG over that time period via the computer. Don't know how the EPA calculates highway @ 26MPG but I do not see myself getting near that unless I get some gains as everything breaks in in a couple thousand miles. Not that I expected that with 3.73s anyways... lol.
Curious to see what those with 3.31 5.0s get mileage wise as well.
7/13/10, 10:57 AM
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I love the car too. It accelerates so quickly it makes everyone else seem slow and pitiful in comparison. It seems like it pulls at 60 MPH harder than most cars pull off the line!
My gas mileage though is small and pitiful. 15-16 MPG seems to be what I'm getting, but my ratio is probably the opposite of yours. There are only a few areas in my commute where I can put it in 6th for any length of time. The rest is just rowing through gears between stop lights or being stuck in 4th or 5th because traffic is going too slow or slowing and accelerating too much. Of course it doesn't help that when I see an opening I decide to let the engine roar a bit.
80/20% city/highway I'd say for me, ~550 miles so it's still in break in technically. Haven't reset the mileage calculator or anything, but I will at 1000 miles.
My gas mileage though is small and pitiful. 15-16 MPG seems to be what I'm getting, but my ratio is probably the opposite of yours. There are only a few areas in my commute where I can put it in 6th for any length of time. The rest is just rowing through gears between stop lights or being stuck in 4th or 5th because traffic is going too slow or slowing and accelerating too much. Of course it doesn't help that when I see an opening I decide to let the engine roar a bit.
80/20% city/highway I'd say for me, ~550 miles so it's still in break in technically. Haven't reset the mileage calculator or anything, but I will at 1000 miles.
7/13/10, 11:41 AM
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I realize that, hence the "Not that I expect that with 3.73s...lol". One thing I am curious about does regard the EPA testing. If a 2011 5.0 Manual with 3.31s is rated at 26 MPG highway, what can someone expect in real world conditions going 80mph down a flat highway?
7/13/10, 11:51 AM
#6
Ok guys what is the best way to "break in" the engine????
7/13/10, 12:18 PM
#7
Mach 1 Member
Beat the hell out of it. How you run the engine in its first 1000 miles is how well the engine will run for the rest of its life. Whatever you do, do NOT go on highway trips and let it sit at 2200 rpm in 6th gear the whole time.
Break-in time is the most fun ever. You get to act like a 16 year old. Except for, hopefully, the crashing it part.
Break-in time is the most fun ever. You get to act like a 16 year old. Except for, hopefully, the crashing it part.
7/13/10, 12:29 PM
#8
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Beat the hell out of it. How you run the engine in its first 1000 miles is how well the engine will run for the rest of its life. Whatever you do, do NOT go on highway trips and let it sit at 2200 rpm in 6th gear the whole time.
Break-in time is the most fun ever. You get to act like a 16 year old. Except for, hopefully, the crashing it part.
Break-in time is the most fun ever. You get to act like a 16 year old. Except for, hopefully, the crashing it part.
7/13/10, 02:12 PM
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Basically what I did was, up until 100 miles on the odometer, no super high loads on the engine. WOT to redline in first gear and WOT to redline in third gear are worlds apart when it comes to how much stress is placed on the driveline. I did a lot of mixed driving - mainly because of where I bought it.
The car was in the middle of Baltimore, MD, which is nothing but stop lights every 1/4 mile. For the first 20 or so miles I was constantly having to stop, get going again, stop, etc etc. All of this of course is very light duty as far as load goes, but still works nicely in terms of making sure everything is seated within the powertrain.
Beyond that, it was the highway all the way home. Speed limit being 65, most people travel at around 80. I would go about 5 miles in 6th, cruising at around 80, drop down to 65, in 5th, run it slightly hard (again, not too much load on the engine) up to 80, drop back down every couple of minutes to 65, repeat.
When I hit 100 miles, I've been treating it like I did my 2008 GT with some 20,000 miles on it. Driving it as hard as I feel like, basically. I'm going to hit 2000 miles this week, and do an oil change to see how well I did.
The car was in the middle of Baltimore, MD, which is nothing but stop lights every 1/4 mile. For the first 20 or so miles I was constantly having to stop, get going again, stop, etc etc. All of this of course is very light duty as far as load goes, but still works nicely in terms of making sure everything is seated within the powertrain.
Beyond that, it was the highway all the way home. Speed limit being 65, most people travel at around 80. I would go about 5 miles in 6th, cruising at around 80, drop down to 65, in 5th, run it slightly hard (again, not too much load on the engine) up to 80, drop back down every couple of minutes to 65, repeat.
When I hit 100 miles, I've been treating it like I did my 2008 GT with some 20,000 miles on it. Driving it as hard as I feel like, basically. I'm going to hit 2000 miles this week, and do an oil change to see how well I did.
7/13/10, 02:51 PM
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The first 100 miles on my car were pretty much taken care of for me, almost. By the time I got it home it was over 100 miles. Dunno how well. I expect there was a little fun time, but I know it's pure highway from the train yard to the dealership. The advice I went with is to drive it the way it'll be driven. Just don't stay on the highway too long, keep the speed varied, and do an early oil change between 500 and 1000 miles.
This suited me pretty well, because my driving style spans the entire RPM range, and that's really what I feel on break in.
And I dunno, 15.2 MPG with pretty much all city driving and 3.73s? Probably pretty close to the actual estimate, given the axle.
This suited me pretty well, because my driving style spans the entire RPM range, and that's really what I feel on break in.
And I dunno, 15.2 MPG with pretty much all city driving and 3.73s? Probably pretty close to the actual estimate, given the axle.
7/13/10, 03:36 PM
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Basically what I did was, up until 100 miles on the odometer, no super high loads on the engine. WOT to redline in first gear and WOT to redline in third gear are worlds apart when it comes to how much stress is placed on the driveline. I did a lot of mixed driving - mainly because of where I bought it.
The car was in the middle of Baltimore, MD, which is nothing but stop lights every 1/4 mile. For the first 20 or so miles I was constantly having to stop, get going again, stop, etc etc. All of this of course is very light duty as far as load goes, but still works nicely in terms of making sure everything is seated within the powertrain.
Beyond that, it was the highway all the way home. Speed limit being 65, most people travel at around 80. I would go about 5 miles in 6th, cruising at around 80, drop down to 65, in 5th, run it slightly hard (again, not too much load on the engine) up to 80, drop back down every couple of minutes to 65, repeat.
When I hit 100 miles, I've been treating it like I did my 2008 GT with some 20,000 miles on it. Driving it as hard as I feel like, basically. I'm going to hit 2000 miles this week, and do an oil change to see how well I did.
The car was in the middle of Baltimore, MD, which is nothing but stop lights every 1/4 mile. For the first 20 or so miles I was constantly having to stop, get going again, stop, etc etc. All of this of course is very light duty as far as load goes, but still works nicely in terms of making sure everything is seated within the powertrain.
Beyond that, it was the highway all the way home. Speed limit being 65, most people travel at around 80. I would go about 5 miles in 6th, cruising at around 80, drop down to 65, in 5th, run it slightly hard (again, not too much load on the engine) up to 80, drop back down every couple of minutes to 65, repeat.
When I hit 100 miles, I've been treating it like I did my 2008 GT with some 20,000 miles on it. Driving it as hard as I feel like, basically. I'm going to hit 2000 miles this week, and do an oil change to see how well I did.
7/13/10, 04:26 PM
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I have let all my coworkers drive my car and they have all hit triple digits in it. My mileage is poor at 16.2 miles per gallon. I only have 382 miles on my car right now. I've read reports of better mileage past 1k miles, but I'm not holding my breath. I didn't buy this car for freaking gas mileage. I have a '98 Civic that gets 33 mpg for that.
7/13/10, 04:40 PM
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I've got 3.31's and have just over 2300 miles on it. I have yet to reach over 15.4 mpg and I don't get on it all the time. I drive pretty much 85/15 - city/hwy. From what I've been reading over the past month or two, it seems the 3.73's are out doing me in gas mileage.
7/13/10, 04:47 PM
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around 21-22 now with 1200 miles and still driving the same as the day I got it. Ive said it before and will again with 2500 miles and cruize I should see 25 easy.
around 21-22 now with 1200 miles and still driving the same as the day I got it. Ive said it before and will again with 2500 miles and cruize I should see 25 easy.
7/13/10, 06:32 PM
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3.73s 21-22mpg w/700 miles. Quite a bit of highway but some redline bouncing. 1st gear is kinda useless. At cruise in town I find it in 5th gear mostly. Its taken some getting used to because my C4 vette would be 3rd or 4th gear in town and 5th gear more than 6th gear on highway.
7/13/10, 11:53 PM
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I have been able to get decent mileage by driving easy. I get a message that suggests a shift point for fuel efficiency. It says go from 1st to 4th. Not sure if anyone else has noticed this or not. I shift from 1st to 4th at around 3000 rpm and then shift to 6th at around 40 mph when I am being fuel conscious. The 5.0 has no problem pulling in 4th even at low speeds. I also rev it through the gears a lot though because it is a badass ride and needs to get broke in properly. When in cruise control at 60 mph in 6th I can get better than 26 mpg on the computer. I have the 3.73 diff and approx 1400 miles on it.
7/14/10, 10:52 AM
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I could be mis-estimating. My gas mileage has been stagnant at 15.2 MPG all week. Just passed 600 miles today. No special driving. Only one or two good stretches of road, but I frequently end up behind people going the speed limit (which never exceeds 50. Today a minivan pulled out in front of me slower than I can go from 0-60 
). Worse the good stretches have lately been dotted with construction zones.
). Worse the good stretches have lately been dotted with construction zones.
Last edited by Lancel; 7/14/10 at 10:54 AM.
7/14/10, 08:03 PM
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I reset it this AM and drove "normally" to work and back, about 50 miles. 80% highway and 20% streets. 17mph.
There is no way in hell I will EVER get 20 MPH in this thing.. not that it matters, but I'd have to drive 48 mph in sixth gear on a flat road for me to get in the 20's I think.
There is no way in hell I will EVER get 20 MPH in this thing.. not that it matters, but I'd have to drive 48 mph in sixth gear on a flat road for me to get in the 20's I think.