2017 fuel economy

I have found I can improve my city MPG by getting on it slightly more aggressive from a stop until I am up to speed. Subjectively it seems to help my overall mileage by 1-1.5MPG


Not a jack rabbit start by any means but not eggshell under the foot acceleration either.
 
Interesting. I remain leery of them because of how much debris they let past, as well as the oil coating of MAF sensor wires they can cause.

I used to run them as well but got tired of the cleaning hassle :)

Replacement filters are relatively cheap these days.... other than the two (dual intake) I have put in my Infiniti
 
OK, I did a REAL WORLD TEST. I reset the dash trip reading and then filled the tank and then reset the trip to zero and calculated it on the refill.

Here is what I got:

DASH DISPLAY = 29.4 MPG
HAND CALCULATION = 29.8 MPG (6.9 Gallons of fuel burned at 208 miles with Costco Top Tier 91 octane fuel)

2016 CX5 GT- AWD - Roof Rack (no cross rails), OEM Mudflaps
  • Continental Tires at 40psi cold
  • 75% Highway - 25% City Driving
  • A/C on about 50% of time
  • A few WOT runs
 
holy crap why are you running 40 PSI in your tires?? You'll see greatly reduced tire life and reduced traction if you always keep them that high.
 
These tires are probably rated 44 cold, so well below the limit, no risk of exploding the tire.
However, might cause uneven wear, with more wear in the center of the tire. Could also cause some reduction in traction.
I too inflate a little bit extra, but only +2.
 
These tires are probably rated 44 cold, so well below the limit, no risk of exploding the tire.
However, might cause uneven wear, with more wear in the center of the tire. Could also cause some reduction in traction.
I too inflate a little bit extra, but only +2.
The OEM Toyo A23 19" tires on GT are rated 51 psi maximum inflation pressure. 40 psi cold is well within safety range. I run 39 psi just trying to get a little better gas mileage and even wear. Factory specs seem always a bit low and would cause wearing outside edges of the tires from my past experience.
 
I failed to notice GT.
44 psi cold is the limit on the 17 inch wheels on OE tires and also for some alternatives.
 
I failed to notice GT.
44 psi cold is the limit on the 17 inch wheels on OE tires and also for some alternatives.
Even for Touring 17" tires, I'd get tires with lighter weight and higher maximum inflation pressure for more fuel efficiency. For example, highly recommended General AltiMax RT43 is a H rated grand touring all-season tire which has 700 A A UTQG, 51 psi maximum inflation pressure, and weighted only 25 lbs. The price tag is around $104.76 each which is very cost effective too.

Just don't forget to add a few more pounds for these 17" 51 psi MIP tires as factory spec of 34 psi is for 44 psi MIP tires.
 
The OEM Toyo A23 19" tires on GT are rated 51 psi maximum inflation pressure. 40 psi cold is well within safety range. I run 39 psi just trying to get a little better gas mileage and even wear. Factory specs seem always a bit low and would cause wearing outside edges of the tires from my past experience.

I run 36psi cold and my tires look beautiful with 22k miles on them so far. 17" rims.
 
Tires are rated for 51 psi max so 40 psi cold is around 44psi hot and well within the specs of the tire.

Many people fail to realize that the tire spec loads are achieved at MAX psi as that is when the tire is the strongest. So if a tire is rated at 1,400 pounds per tire, that rating is achieved at MAX PSI.

I've driven trucks and heavy duty vehicles and they always run max psi when hauling and towing.

Low psi is what destroys tires and causes them to overheat and blow out. It's counter-intuitive but low psi makes tires blow up, not max psi.

At 44psi HOT, I get excellent wear and traction and great MPG. When I go under 40psi HOT, the tires wear faster and my MPG will drop.
 
Tires are rated for 51 psi max so 40 psi cold is around 44psi hot and well within the specs of the tire.

Many people fail to realize that the tire spec loads are achieved at MAX psi as that is when the tire is the strongest. So if a tire is rated at 1,400 pounds per tire, that rating is achieved at MAX PSI.

I've driven trucks and heavy duty vehicles and they always run max psi when hauling and towing.

Low psi is what destroys tires and causes them to overheat and blow out. It's counter-intuitive but low psi makes tires blow up, not max psi.

At 44psi HOT, I get excellent wear and traction and great MPG. When I go under 40psi HOT, the tires wear faster and my MPG will drop.

Interesting. I have consistently gotten better performance from my cars using correct recommended tire pressure. Especially in the handling department. Contact patch matters a lot for handling.
 
Everywhere I read about this on the web, it says to use the recommended pressure on the driver side door:
  • Pressure lower than recommended definitely destroys tires, including the sidewalls, and increases fuel economy.
  • Only the car manufacturer, not the tire manufacturer, know what is the recommended pressure, because the tire is designed for a range of loads.
  • If the pressure is too high for the load, the tire becomes more rounded which makes the contact patch smaller and in the center of the tread.
  • When so, traction is reduced and the tire will wear more at the center. Reduced traction means that it can become more dangerous to drive on wet/icy surfaces and on high speed turns.

Do you know something different? Why second guess the recommendation made by Mazda (unless you really put more load on the vehicle)?
 
Everywhere I read about this on the web, it says to use the recommended pressure on the driver side door:
  • Pressure lower than recommended definitely destroys tires, including the sidewalls, and increases fuel economy.
  • Only the car manufacturer, not the tire manufacturer, know what is the recommended pressure, because the tire is designed for a range of loads.
  • If the pressure is too high for the load, the tire becomes more rounded which makes the contact patch smaller and in the center of the tread.
  • When so, traction is reduced and the tire will wear more at the center. Reduced traction means that it can become more dangerous to drive on wet/icy surfaces and on high speed turns.

Do you know something different? Why second guess the recommendation made by Mazda (unless you really put more load on the vehicle)?

The only caveat is sustained high-speed and/or towing, and the manufacturer has guidelines for that, too, for the vehicles that it pertains to. The CX-5 isn't even close to being one of them though, lol
 
Tires are rated for 51 psi max so 40 psi cold is around 44psi hot and well within the specs of the tire.

Many people fail to realize that the tire spec loads are achieved at MAX psi as that is when the tire is the strongest. So if a tire is rated at 1,400 pounds per tire, that rating is achieved at MAX PSI.

I've driven trucks and heavy duty vehicles and they always run max psi when hauling and towing.

Low psi is what destroys tires and causes them to overheat and blow out. It's counter-intuitive but low psi makes tires blow up, not max psi.

At 44psi HOT, I get excellent wear and traction and great MPG. When I go under 40psi HOT, the tires wear faster and my MPG will drop.
This is more true than most people realize, max psi will just cause them to balloon and wear more in the middle and if you get too high you might get a bubble somewhere in the sidewall if you hit the right bump.
 
This is more true than most people realize, max psi will just cause them to balloon and wear more in the middle and if you get too high you might get a bubble somewhere in the sidewall if you hit the right bump.

It also kills traction and makes a car "twitchy", significantly lowers ability to corner, and makes it ride rough.
 
It also kills traction and makes a car "twitchy", significantly lowers ability to corner, and makes it ride rough.

..because you're no longer on the entire width of your tread, with lower pressures you are literally riding on the outside edges of your tires. Especially bad in wet weather, it will add to hydroplaning.
 
Do you know something different? Why second guess the recommendation made by Mazda (unless you really put more load on the vehicle)?

Mazda did NOT make the tires for this vehicle, they outsourced it to Toyo. Those door recommendations belong to that Toyo tire and nothing else. When you replace the tires with a different tire brand/model/style, then that door tag recommendation no longer applies.

I use Continental Tires that recommend a 35-40 psi COLD pressure in them from the tire manufacturer. They engineered and designed the tire so I go by that spec. Not some generic, arbitrary, door tag that applies to the factory OEM Toyo tire which is no longer on the vehicle.

LOW TIRE PRESSURE:
  • Most drivers lose from 20% to as much as 50% of tire tread life due to underinflation
  • If a vehicle's tires are underinflated by only 6 psi it could lead to tire failure
  • Lower inflation pressure will allow the tire to deflect more as it rolls.
  • Lower inflation builds up internal heat, increase rolling resistance and cause a reduction in fuel economy of up to 10%
  • Lower inflation causes a significant loss of steering precision and cornering stability
  • Tire blowouts during the summer are caused by underinflated tires overheating and the sidewall begins to fail, resulting in a blow out

HIGHER TIRE PRESSURE:

  • Higher inflation pressures provides an improvement in steering response and cornering stability (This is why participants who use street tires in autocrosses, track events and road races run higher than normal inflation pressures.)
  • Better MPG due to less rolling resistance
  • If towing or loaded, higher pressure is safer since the tires strength is determined by PSI. The higher the PSI, the stronger the tire.
  • Higher pressure protects the sidewall for being damaged since the tire sidewall is not rolling on the ground
 
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Interesting. I have consistently gotten better performance from my cars using correct recommended tire pressure.

Where is that "correct recommended tire pressure" documentation found?

IF you answer (door jamb), you are incorrect.

Since that only applies to the OEM factory tire. Once you change that tire, everything changes, even if you keep the same size tire. Each manufacturer has its own specs and recommendations. Many people fail to understand that the door jamb tag only applies to the original factory installed tires.
 
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