Jump to content

Custom Search




Welcome to the C-MAX Hybrid Forum


Sign In  Log in with Facebook

Create Account
Welcome to the C-MAX Hybrid Forum. You must register to create topics or post in our community, but don't worry this is a simple free process that requires minimal information for you to signup. Here's some member benefits:
  • Start new topics and reply to others
  • Subscribe to topics and forums to get email updates
  • Get your own profile page and make new friends
  • Send personal messages to other members
  • Create photo albums and post images. . .more!
Click here to create an account now
 
Guest Message by DevFuse

Get you C-MAX Hybrid Registered in the official Ford Authorized Registry. More here.


Photo

How do I maximize Highway MPG?

Highway MPG

  • Please log in to reply
69 replies to this topic

#41 OFFLINE   Adrian_L

Adrian_L

    C-Max Hybrid Member

  • C-MAX Hybrid Member
  • 675 posts
  • Region:Canada British Columbia
  • LocationVancouver, BC
  • My C-MAX's Year:2013
  • Current Vehicle:2013 SEL

Posted 02 March 2015 - 01:04 PM

That sounds reasonable, considering the plethora of tire manufacturers. 

 

Ford deflated my tires to 40 psi when I had my first service.  So I put them back up to 45. 


  • ptjones likes this







Lose this advertisement by becoming a member. Click here to create a free account.


#42 OFFLINE   SPL Tech

SPL Tech

    C-Max Hybrid Member

  • C-MAX Hybrid Member
  • 286 posts
  • Region:Decline
  • Locationhome
  • My C-MAX's Year:Decline
  • Current Vehicle:c-max 2013 SL

Posted 03 March 2015 - 02:03 AM


 

As kblast notes, the "correct inflation pressure ... specified by the vehicle manufacturer" is what got Ford Explorer drivers killed.

 

And you dont think tire manufacturers havent gotten it wrong too? Millions upon millions of auto tires have been recalled, and most of those were recalls relating to reasons having nothing to do with the auto manufacturer.

I disagree that the auto manufacturer is not the best resource to determine the tire pressure. Here is why. The tire manufacturer has no idea what vehicle you plan to put the tires on, so there is no possible way they can recommend you an optimal inflation value. A 2000 lb car is going to have a MUCH lower optimal tire pressure value than a 4000 lb car with the exact same tires. Choosing the wrong tire pressure WILL cause increased wear, reduced traction, higher risk of deflation, high risk of rollover, ect, and the right pressure depends heavily on the vehicle that the tires are attached to.


Edited by SPL Tech, 03 March 2015 - 02:04 AM.

  • scottwood2, Adrian_L and Bugblndr like this

#43 OFFLINE   Adrian_L

Adrian_L

    C-Max Hybrid Member

  • C-MAX Hybrid Member
  • 675 posts
  • Region:Canada British Columbia
  • LocationVancouver, BC
  • My C-MAX's Year:2013
  • Current Vehicle:2013 SEL

Posted 03 March 2015 - 01:22 PM

At the risk of flip-flopping, that makes complete sense.  

 

Filling your tires to 50 psi is probably not going to do much harm, but arriving at that number from a non-scientific "feeling" that the car rides better is kind of like picking oil based on how it feels between your fingers.


Edited by Adrian_L, 03 March 2015 - 01:33 PM.


#44 OFFLINE   SStoner

SStoner

    New Member

  • Inactive
  • Pip
  • 16 posts
  • Region:U.S. Pacific Coast
  • LocationWA
  • My C-MAX's Year:2014
  • Current Vehicle:CMAX Hybrid

Posted 03 March 2015 - 04:02 PM

Tires have a stamped max PSI rating on the sidewall. Our factory tires to rated @ 51 psi.



#45 OFFLINE   ptjones

ptjones

    C-Max Hybrid Member

  • C-MAX Hybrid Platinum Member
  • 3,112 posts
  • Region:U.S. Southern Atlantic
  • LocationNewnan, GA
  • My C-MAX's Year:2013
  • Current Vehicle:2013 C-MAX SEL

Posted 03 March 2015 - 05:31 PM

To me the right tire pressure to use would be the tire pressure that gives even tire wear, 50PSI for the CMAX from my experience. Which is below 51PSI for our Michelin's, to have lower is waste of gas. IMO

Paul
  • Smiling Jack and SStoner like this

#46 OFFLINE   edward stewart

edward stewart

    New Member

  • C-MAX Hybrid Member
  • 20 posts
  • Region:U.S. Southern Atlantic
  • LocationNorth of Atlanta GA
  • My C-MAX's Year:2014
  • Current Vehicle:c-max se

Posted 19 June 2015 - 09:28 AM

Well looking at the debate on the tire pressure, everyone might find this interesting. I keep my car at the ratted psi for the car. In this traffic you never know when someone will cut you off in your comfort zone or when you'll be driving on wet roads. 

 

Well anyway, the last time I had my card serviced at a Ford Dealership, back in March, my tires were inflated to 45psi. vs. th 40 on the door. I was not a happy camper, still need to talk to them when I go back in about 1k miles.... but the statement I got when I took it in was they set the car to spec. Happy camper when I discovered they had upgraded to 0w-20... can't really find anything on the tires... ya this is in another thread, but thought I would pass it along in this one.  



#47 OFFLINE   edward stewart

edward stewart

    New Member

  • C-MAX Hybrid Member
  • 20 posts
  • Region:U.S. Southern Atlantic
  • LocationNorth of Atlanta GA
  • My C-MAX's Year:2014
  • Current Vehicle:c-max se

Posted 11 July 2015 - 09:22 AM

Just had the car serviced yesterday. Inquired about getting paperwork on a psi update paperwork.... got the ... The pressure gauge must have been faulty, we will test with two different pressure gauge excuses. 

 

Some please remind me why I'm paying premium prices at a dealership, vs, having my co-workers at Wal-Mart do it in the automotive department (17 year associate, there might be a incident or 2 year at my store.) ???? I could have slept in, checked in my car at work, clocked in, and left at the end of my sift. 3 hours of my life gone. 

 

Do the dealerships even check the fluid level's in the CVT, plus color to see if its burned up, or do they just look for leaks???? Is there a after market solution to adding a dipstick to the CVT????


Edited by edward stewart, 11 July 2015 - 09:37 AM.


#48 OFFLINE   ptjones

ptjones

    C-Max Hybrid Member

  • C-MAX Hybrid Platinum Member
  • 3,112 posts
  • Region:U.S. Southern Atlantic
  • LocationNewnan, GA
  • My C-MAX's Year:2013
  • Current Vehicle:2013 C-MAX SEL

Posted 11 July 2015 - 03:23 PM

FORD will set the PSI to what is in the door jam unless you tell them different. I'm pretty sure to say that my Trans Fluid was never checked, there were no leaks so it must be good. ;)

 

Paul



#49 OFFLINE   cheezy

cheezy

    C-Max Hybrid Member

  • Inactive
  • PipPip
  • 58 posts
  • Region:U.S. Great Lakes
  • LocationMW
  • My C-MAX's Year:2013
  • Current Vehicle:C-Max

Posted 16 July 2015 - 07:05 AM

Brand new owner here looking to take a 300 mile round trip on the highway.
Any suggestions for maximizing MPG @ 65 mph?
Thx

 

45-50 PSI in tires, use ethanol free fuel, have the oil level in your car at the halfway point between the 'stick marks of High & Low.

 

If your commute is nice and level, NOT hilly, use the Eco-cruise function.

 

Enjoy.

 

Our Dealer I just picked the car up from had the Oil level over the "Full" mark and the front tires were both under 40 P.S.I. Simple fixes. 

 

Enjoy!!



#50 OFFLINE   Bugblndr

Bugblndr

    C-Max Hybrid Member

  • C-MAX Hybrid Member
  • 98 posts
  • Region:Canada Ontario
  • LocationGTA
  • My C-MAX's Year:2015
  • Current Vehicle:C-Max

Posted 16 July 2015 - 08:44 AM

Some please remind me why I'm paying premium prices at a dealership, vs, having my co-workers at Wal-Mart do it in the automotive department (17 year associate, there might be a incident or 2 year at my store.) ???? I could have slept in, checked in my car at work, clocked in, and left at the end of my sift. 3 hours of my life gone. 

 

 

Good question. My 2011 Toyota Highlander Hybrid never went to the dealer after I picked it up. 85,000 miles, 4 years, not one visit to a Toyota service department. 

 

I had all maintenance done at a local Jiffy Lube, or an independent garage across the street from my work, or the shop my wife worked at.  I saved a ton of money and sacrificed nothing by doing so IMO.

 

My C-Max will definitely have at least it's first service done at the Ford dealer since there's already been a recall on it.  My wife works at the dealer I bought it from so the pricing should be reasonable at least.


  • ptjones likes this

#51 OFFLINE   cheezy

cheezy

    C-Max Hybrid Member

  • Inactive
  • PipPip
  • 58 posts
  • Region:U.S. Great Lakes
  • LocationMW
  • My C-MAX's Year:2013
  • Current Vehicle:C-Max

Posted 16 July 2015 - 09:49 AM

45-50 PSI in tires, use ethanol free fuel, have the oil level in your car at the halfway point between the 'stick marks of High & Low.

 

If your commute is nice and level, NOT hilly, use the Eco-cruise function.

 

Enjoy.

 

Our Dealer I just picked the car up from had the Oil level over the "Full" mark and the front tires were both under 40 P.S.I. Simple fixes. 

 

Enjoy!!

 

 

 

If you want the easiest way to remove oil from the Dealer's possible overfill, grab yourself a Pella oil vacuum pump from any mariner supply shop online; straw hose goes down the dipstick hole, and vacs oil out. Great for complete oil changes as well. 


Edited by cheezy, 16 July 2015 - 09:49 AM.


#52 OFFLINE   ptjones

ptjones

    C-Max Hybrid Member

  • C-MAX Hybrid Platinum Member
  • 3,112 posts
  • Region:U.S. Southern Atlantic
  • LocationNewnan, GA
  • My C-MAX's Year:2013
  • Current Vehicle:2013 C-MAX SEL

Posted 16 July 2015 - 10:26 AM

Then again you could remove ICE cover and drain out some oil from drain plug which doesn't require spending any money. Easier to do when the oil is cold. :)

 

Paul



#53 OFFLINE   Taz

Taz

    New Member

  • C-MAX Hybrid Member
  • 38 posts
  • Region:Decline
  • LocationMPLS and LA
  • My C-MAX's Year:2014
  • Current Vehicle:Avalon Hybrid

Posted 16 July 2015 - 01:11 PM

One other thing to consider as well besides mileage, is resistance to hydroplaning. There is a direct relationship between psi and speed at which a tire hydroplanes. From my flying days I was taught to take the square root of the PSI, multiply it time 9 and the will equal knots at which the tire can begin to hydroplane.

 

Since most of you don’t deal with knots for speed, a quicker, but not perfect version, is to take the square root of the PSI and multiply it times 10 to get MPH.

 

30psi =  ~55mph

35psi =  ~59mph

 

40psi = ~63 mph

45psi = ~67 mph

 

50psi = ~71 mph

55psi = ~74 mph

 

As you can see, even just being mildly underinflated can put you at risk of easily encountering hydroplaning in wet weather. At the high end, you are crazy to drive much over 65 mph in the rain with stock tire pressures.


  • ptjones likes this

#54 OFFLINE   fbov

fbov

    C-Max Hybrid Member

  • C-MAX Hybrid Platinum Member
  • 1,315 posts
  • Region:U.S. Northeast
  • LocationRochester, NY
  • My C-MAX's Year:2013
  • Current Vehicle:C-Max Hybrid

Posted 17 July 2015 - 10:40 AM

One other thing to consider as well besides mileage, is resistance to hydroplaning. There is a direct relationship between psi and speed at which a tire hydroplanes. From my flying days ....

... At the high end, you are crazy to drive much over 65 mph in the rain with stock tire pressures.

While generally true, especially over a wide pressure range, you may want to revisit the assumptions before extending it to automobile tires.

 

Speed

Planes land fast and slow down. Cars start at rest and speed up. The latter has the option of sensing a reduction in grip before it's lost. The former has to make an estimate in the air, with no good alternatives to landing. Expect a very conservative rule-of-thumb as a result.

 

Tires

Plane tires are designed for drag racing - 0-to-100 MPH in 0.5 seconds! As such, they are crowned, so only the center makes contact initially. That makes tire pressure a direct driver of contact patch size, and hydroplaning is very sensitive to contact patch size.

 

Tread

Drag racing tires don't have much tread. Neither do the aviation tires I see in a quick search. That's a direct result of landing stresses, which no car tire will every see in normal use. If you've ever driven the famous Italian racing tire, the "Baldini," you know how valuable tread is in the rain.

 

And it's tread that makes your last statement pure nonsense. Tread depth and road water load/drainage are far stronger effects that tire pressure in the 40-50psi range. C-Maxers who choose to retain OEM pressures are not in additional danger of hydroplaning as a result of that choice.

 

So, your post has good stuff in it, but I don't see how it applies.

 

HAve fun,

Frank



#55 OFFLINE   ptjones

ptjones

    C-Max Hybrid Member

  • C-MAX Hybrid Platinum Member
  • 3,112 posts
  • Region:U.S. Southern Atlantic
  • LocationNewnan, GA
  • My C-MAX's Year:2013
  • Current Vehicle:2013 C-MAX SEL

Posted 17 July 2015 - 01:44 PM

Assuming tire has significant tread (not Baldini :) ) the higher the pressure/smaller contact area would be less affected to Hydroplaning than  less pressure would be.  When I first had MADMAX  using 38psi  I ran through a  deep puddle during a rain storm and almost had the steering wheel ripped from my hands, WOW that was scary.  Now at 50psi it's not so bad. :shift:

 

Paul



#56 OFFLINE   Taz

Taz

    New Member

  • C-MAX Hybrid Member
  • 38 posts
  • Region:Decline
  • LocationMPLS and LA
  • My C-MAX's Year:2014
  • Current Vehicle:Avalon Hybrid

Posted 19 July 2015 - 09:26 PM

And it's tread that makes your last statement pure nonsense. Tread depth and road water load/drainage are far stronger effects that tire pressure in the 40-50psi range. C-Maxers who choose to retain OEM pressures are not in additional danger of hydroplaning as a result of that choice.

 

HAve fun,

Frank

 

Many roads have inadequate drainage. Maybe at one time they did but I have been on many highways, all over the US, where the trucks have created "ruts" where there is a significant amount of standing water when it rains. I have been in some states where it appears the people who designed the roads put absolutely no thought into drainage. A few extra PSI can make a difference. 

 

As for tread depth, it is in a state of continually decreasing. I prefer to err on the safe side. I subscribe to the adage "There are old pilots and bold pilots, and no old, bold pilots." I have thousands of hours in aircraft from sub-sonic to Mach 2+. I never wait for my tires to get down to the treadwear indicators. Considering I am often driving in relatively extreme climates it isn't worth the risk to me or my family. Like most things, tires are a compromise. Unfortunately you don't always know what the compromises were until it is too late.

 

Even with almost full tread depth (3k miles on the stock tires and pressures) I encountered significant hydroplaning at about 60 mph outside of ABQ on a recent trip. There was standing water on I-40 and thankfully I had slowed down from about 80 when I first noticed the wet roads. The truck in front of me didn't. He must have rolled 3 or 4 times after losing control while spewing parts all over the highway. I don't know if he and his passengers survived or not. If I had maintained my previous speed I am not sure how it would have turned out for my wife and I. As it was, I lost total control for about a second or so. So while the maxims I learned regarding fly may be conservative, they likely saved our lives.

 

At a minimum it will at least have people here thinking about this topic whereas it was never mentioned before. At least with an aircraft landing at high speeds on runways, I was not dependent on the tires generally for directional control until I lost authority with the control surfaces. I don't have the option of adding a little rudder to compensate for a skid.


  • JAZ and ptjones like this

#57 OFFLINE   ptjones

ptjones

    C-Max Hybrid Member

  • C-MAX Hybrid Platinum Member
  • 3,112 posts
  • Region:U.S. Southern Atlantic
  • LocationNewnan, GA
  • My C-MAX's Year:2013
  • Current Vehicle:2013 C-MAX SEL

Posted 20 July 2015 - 09:23 AM

I agree with Taz having flown my own airplane for 13yrs. and also know about the "ruts" on I-40. :)

 

Paul



#58 OFFLINE   Redshift

Redshift

    New Member

  • C-MAX Hybrid Member
  • 42 posts
  • Region:U.S. Pacific Coast
  • LocationTacoma, WA
  • My C-MAX's Year:2015
  • Current Vehicle:C-Max

Posted 09 September 2015 - 12:52 PM

One other thing to consider as well besides mileage, is resistance to hydroplaning. There is a direct relationship between psi and speed at which a tire hydroplanes. From my flying days I was taught to take the square root of the PSI, multiply it time 9 and the will equal knots at which the tire can begin to hydroplane.

 

Since most of you don’t deal with knots for speed, a quicker, but not perfect version, is to take the square root of the PSI and multiply it times 10 to get MPH.

 

30psi =  ~55mph

35psi =  ~59mph

 

40psi = ~63 mph

45psi = ~67 mph

 

50psi = ~71 mph

55psi = ~74 mph

 

As you can see, even just being mildly underinflated can put you at risk of easily encountering hydroplaning in wet weather. At the high end, you are crazy to drive much over 65 mph in the rain with stock tire pressures.

Sorry, that's a silly statement. I took a 5000+ trip this summer. The speed limits in Wyoming and South Dakota were just raised to 80mph. I drove my C-Max at 85 mph. It was raining (torrential) and I never had any kind of a traction problem. My tires are at 40lbs, factory setting.



#59 OFFLINE   Taz

Taz

    New Member

  • C-MAX Hybrid Member
  • 38 posts
  • Region:Decline
  • LocationMPLS and LA
  • My C-MAX's Year:2014
  • Current Vehicle:Avalon Hybrid

Posted 09 September 2015 - 03:53 PM

There is more to hydroplanning than just tire pressure. If the road is grooved like some highways that lessens the risk. The amount of tread on the tire, the siping, etc.

 

Whether you want to believe it or not, there is a relationship between tire pressure and hydroplaning. You don't have to believe me though, go here.

 

http://www.nhtsa.gov...38/part5.6.html

 

and here 

 

https://www.tirerack...ge.jsp?techid=3



#60 OFFLINE   fbov

fbov

    C-Max Hybrid Member

  • C-MAX Hybrid Platinum Member
  • 1,315 posts
  • Region:U.S. Northeast
  • LocationRochester, NY
  • My C-MAX's Year:2013
  • Current Vehicle:C-Max Hybrid

Posted 10 September 2015 - 12:39 PM

There is more to hydroplanning than just tire pressure. If the road is grooved like some highways that lessens the risk. The amount of tread on the tire, the siping, etc.

 

Whether you want to believe it or not, there is a relationship between tire pressure and hydroplaning. You don't have to believe me though, go here.

 

http://www.nhtsa.gov...38/part5.6.html

 

and here 

 

https://www.tirerack...ge.jsp?techid=3

Just to be clear here, both of these links deals with the dangers of under-inflation. We're discussing the opposite.

 

Is there any reason not to increase tire pressure from door placard values to tire sidewall values?

 

Have fun,

Frank


  • ptjones and C-MaxSea like this






Custom Search




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

Privacy Policy TERMS OF SERVICE ·