Optimal cruising MPG

[Whiter0se]

Has anyone figured out what the optimal cruising MPGs are? It looks like if I’m on a flat road, going somewhere in between 35-50 MPG, the MPG counter will stay in around 40MPG. On the highway, I’m usually at 55mph or 60mph with some upgrades or downgrades along the way, I’ll usually be around the 25ish mark for MPG.

This is on a 2019 touring. NA engine.

 

[Kaps]

I can't see what model you have but Gen1 CX5 cruising around 55-60 mpg with a Moly or full synthetic + 2 psi more than recommended should get you close to 33 mpg imho. If your distance is long enough you should be able to hit 36+ on good days.
A good moly makes a huge difference. The crap my dealer put it pushed my mpgs in 26 range. I got Mobil1 full syn. and on day one after 30 miles of driving I am sitting at 29.5 mpg.

Subtract 1-2 mpg for Gen2 17 or newer CX5s. I don't know what Mazda has done - the new CX-30 gets 24 City - 31 Hwy mpg - that is great mpg in 2012. Not in 2019.

 

[ColoradoDriver]

I can't see what model you have but Gen1 CX5 cruising around 55-60 mpg with a Moly or full synthetic + 2 psi more than recommended should get you close to 33 mpg imho. If your distance is long enough you should be able to hit 36+ on good days.
A good moly makes a huge difference. The crap my dealer put it pushed my mpgs in 26 range. I got Mobil1 full syn. and on day one after 30 miles of driving I am sitting at 29.5 mpg.

Subtract 1-2 mpg for Gen2 17 or newer CX5s. I don't know what Mazda has done - the new CX-30 gets 24 City - 31 Hwy mpg - that is great mpg in 2012. Not in 2019.

FWD numbers?

 

[ruthrj]

My ‘13 2.0 FWD fits those notes above to a T. Somehow on today’s 200 mile drive I averaged 36 MPG. I’ve never achieved an average that good. That was with speeds around 60-65, no more than 70 at times. Kind of hilly but nothing crazy (Huntsville AL to Chattanooga TN). 73k miles on the odometer with Mobil1 Advanced Fuel Economy oil.

 

[Pipemajor]

Crossovers such as the CX-5 aren't very aerodynamic so speed really kills MPG numbers. I used to track my mileage on the Fuelly app and found optimum cruising speed is around 50-55mph for an AWD version. I was able to hit 34mpg on a trip during summer months at that cruising speed.

Remember that drag increases by the square of speed increase so if you are a lead foot - expect poor MPG performance.

 

[Avoidin Deer]

I've thought of picking out a straight stretch of road to drive up & down at different speeds to see what the Instant MPG readout says for each rate (not that it's valid discrete data, but it would be good relative data), but it's not gonna change the way I drive. If I'm on a 70 MPH road, I'm not gonna do 55 It might be interesting to know how much doing 65MPH when I'm on a 55MPH road costs me out-of pocket, but wouldn't likely change my habits.

Here's an interesting article that discusses what Pipemajor said, in greater depth on the physics behind vehicle size and profile, and optimum MPG speed.

What speed should I drive to get maximum fuel efficiency? | HowStuffWorks

I've got a Reserve, and drive on such winding and hilly rural back roads that there's little I can do to get great mileage (and there's lots that I do to kill it!) I've given up the quest in exchange for miles of smiles.

 

[Whiter0se]

I've got a Reserve, and drive on such winding and hilly rural back roads that there's little I can do to get great mileage (and there's lots that I do to kill it!) I've given up the quest in exchange for miles of smiles.

Oh, I can relate to this. There’s times where on a stretch of road, I just have to exchange some MPGs for a quick adrenaline rush. Snowy parking lots included of course.

 

[CX_FIVER]

My first car was a 63 1/2 Ford with a 427cu in engine. MPG with the 2 4 barrel carbs was around 8 MPG. Premium gas was around 38 cents per gallon. Cost around .05/mile. I stayed broke but smiled
every time I bought my $2.00 worth of gas.

Now, we have a Signature and the turbo brings smiles to my face, too. Figure around 25 mpg and current cost $2.25 per gallon or .09/mile.

Big difference....my salary in 1963 was $6,000/year.

 

[raj55]

I get 7.7 lit/100km, same as 30.5 MPG in mixed driving. I have a 2017 CX-5 with non turbo 2 lit engine.

 

[Avoidin Deer]

My first car was a 63 1/2 Ford with a 427cu in engine. MPG with the 2 4 barrel carbs was around 8 MPG. Premium gas was around 38 cents per gallon. Cost around .05/mile. I stayed broke but smiled
every time I bought my $2.00 worth of gas.

Now, we have a Signature and the turbo brings smiles to my face, too. Figure around 25 mpg and current cost $2.25 per gallon or .09/mile.

Big difference....my salary in 1963 was $6,000/year.

I had a '63 Lincoln. I used to get Christmas cards from OPEC.

 

[Unobtanium]

I dunno. I cruise at around 75-80 and average 27-28mpg doing so, so am content. Turbo.

 

[erhayes]

The speed where the transmission drops into 6th gear with the 2.5NA engine is the optimal speed for best mileage but, not practical in open highway driving. . Ed

 

[Mazdiod2]

I have found that when the throttle is around 30 TPS or less my mpg is pretty close to the rated 35mpg for the 2.0L w 6M as along as my road speed is in the 60s or better. The greater the ground speed for a particular TPS the better the mpg.

If terrain allows me to cruise at highway speeds w a lower TPS. ie the mid to high 20s. then the the economy is much better and can get into the 40s--for that section not overall.

If the TPS is higher such as mid to higher 30s TPS. the economy drops into the 20s.

I would guess the ground speed w 30TPS on level ground is something in the mid 60s but its hard to determine wo test equipment and a wind-free and hill-less test range.

The manual for my fisrt car--VW beagle- cited a test run of 60mph @59'F would acheive 26mpg but modern CAFE tests are much different and are supposed to represent typical driving not steady state.

I consider my cx5 a true economy car even though it is a raised hatchback/pseudoSUV. I think the low weight per cubic foot of storage is unparalleled although the newest Honda is impressive.

I think the underbody panels must help MPG plus the cx5 has a low curb weight.

 

[erhayes]

TPS ?

 

[Mazdiod2]

Trottlr position sensor reported as % on scangauge.

I might recommend the OP try scangauge as it can help acheive better mpg. They have two versions and their are other obii port scanners such ad Ultragauge.

 

[CX_FIVER]

I had a '63 Lincoln. I used to get Christmas cards from OPEC.

Did your 63 Lincoln have suicide doors?

 

[Avoidin Deer]

Did your 63 Lincoln have suicide doors?

Yup.

I loved that car. Running over a Volkswagen was nothing more that a small pothole in that boat.

 

[Kaps]

FWD numbers?

Yes

 

[Apollothedog]

I have a long commute to work much of it on a relative flat highway. Roughly 35 miles on this highway. Typically I keep the cruise control at 78 and average 22-23 MPG. Yesterday I set the Cruise to 65 (actual speed limit) and hit 30 MPG. Big difference, I have a GTR.

 

[Avoidin Deer]

I have a long commute to work much of it on a relative flat highway. Roughly 35 miles on this highway. Typically I keep the cruise control at 78 and average 22-23 MPG. Yesterday I set the Cruise to 65 (actual speed limit) and hit 30 MPG. Big difference, I have a GTR.

That's interesting to see that mileage at 65MPH.

I would have thought 55MPH to be optimum, declining after that.

I agree that the higher speeds are a real mileage-killer. These cars are screaming for a lower highway gear.

edit to add: So assuming your total commute is 40 miles...

At 23 MPG and $3/gallon gas, you'd spend $52/week on gas.
At 30 MPG and $3/gallon gas, you'd spend $40/week on gas.

At 50 weeks a year commuting, you would save about $600 doing the slower speed, or $50/month, and each one-way commute would take an extra 6 minutes. I guess the intangible would be whether or not you could tolerate everyone else flying past you two trips a day, or if you were a hazard by not going with the flow..

Are you burning 93 octane? I keep track of every tank of gas, and on average get 1.6 MPG more out of 93 in my Reserve (although I've only burned 3 tanks of 87 octane). The actual mileage gap is likely to be greater, since those tanks of 87 were on top of partial tanks of 93. It's not enough of a spread to pay for the difference, but there are some places here in the sticks where I really wind the thing out in Manual transmission mode, so I spring for the good stuff.