| t2188na |
Hello,
I'm confused about what to inflate my Michelin Cross Terrains.
Dealer says go with Honda recommended but my 2003 of course did not come with these tires.
Question: Summer Vacation highway driving PSI?
City Driving PSI?
Thanks
NJA, Michigan |
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| humanoid |
| It doesn't matter the brand, just follow what it says in the manual or the driver's side door jam. |
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| rockman19762001 |
| Door jam says 30 or 32 psi, I did not like the soft ride, or more accurately my wife did not like the ride and handling. I have run 35 psi in the Cross Terrains, no problems with un-even wear, and I like the slightly firmer ride. I also switched to Nitrogen, which gave about 1.5 mile per gallon increase on average mile per gallon on the highway. I track my mileage on www.GasBuddy.com for all my personal vehicles. I hope this is helpful. |
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| A6Pilot |
quote:
Originally posted by rockman19762001 I also switched to Nitrogen, which gave about 1.5 mile per gallon increase on average mile per gallon on the highway. [/B]
There are a lot of us who are curious about this statement. So you're saying that using nitrogen will increase mileage about 8-10% or so? How do you suppose that works?
Too bad the engineers at Honda, or GM, etc., haven't figured that one out. In a world where the average power train engineer would sell his first born for a .5 mpg increase, why were these guys so dense to have missed something as simple as inflating tires with nitrogen? On the other hand, they sure blew it by not installing the Turbonator.
Tell us more....... |
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| t2188na |
Yes,
The information was helpful.
Best regards,
NJA |
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| youbetcha |
quote:
Originally posted by rockman19762001
I also switched to Nitrogen, which gave about 1.5 mile per gallon increase on average mile per gallon on the highway.
I use a special 80% Nitrogen mix. It is called "outside air" |
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| N_Jay |
quote:
Originally posted by youbetcha
I use a special 80% Nitrogen mix. It is called "outside air"
What, you don't buy your "reference air"?
P.S. Mileage increases from Nitrogen are pure BS.
Mileage increases from increased inflation (or proper inflation, if they were under-inflated) are real.
The safe range is to use the factory recommendation as the minimum, and the tire side wall rating as the maximum.
Anywhere in between is fine, the higher the better except for ride comfort.
It is best to assume your (and others) gauges are off by up to 2 PSI, so anywhere from 2 PSI above the door sticker to 2 PSI below the sidewall.
Have fun. |
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| rockman19762001 |
Nitrogen pressure is more consistent than normal air pressure, because air typically contains varying amounts of moisture due to changes in the relative humidity during a given day. Water causes air to be inconsistent in its rate of expansion and contraction. Allowing the tire to run slightly cooler than a tire filled with air, and more consistent expansion and contraction when the tire cools. Other than that I have no other idea for going with nitrogen. But, after the local Ford Dealerships quick change locale switched out the air for nitrogen for free, I thought who cares.
Then on the twice a month trip to Dallas , I saw my average miles per gallon go from around 22 to just slightly below 24 miles per gallon, always driving on cruise at 75mph. Other than the mileage on the engine, which means that the Honda Pilot 03 engine was finally broken in at 100,000 miles. I have been using the same oil Ford's 5/20 at each oil change, the only other change I had made to the Pilot was going with the nitrogen in the tires. So suck on it. |
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| A6Pilot |
quote:
Originally posted by rockman19762001
the only other change I had made to the Pilot was going with the nitrogen in the tires. So suck on it.
P T Barnum, are to listening? |
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| N_Jay |
quote:
Originally posted by rockman19762001
. . . the only other change I had made to the Pilot was going with the nitrogen in the tires. So suck on it.
Since you went to Nitrogen and the dealer filled the tires, are you sure that the pressures are the same?
I danced yesterday and it rained.
I did not do anything else differently. :4:
I won't bother asking how many tanks is the drive to Dallas?
or, what has been the range of MPG readings on previous trips?
etc, etc. etc. |
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| youbetcha |
quote:
Originally posted by rockman19762001
So suck on it.
Was this really necessary?
Your posting footer reads "The greatest strength is gentleness." |
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| xGS |
quote:
Originally posted by N_Jay
The safe range is to use the factory recommendation as the minimum, and the tire side wall rating as the maximum.
Anywhere in between is fine, the higher the better except for ride comfort.
What you imply is that ride comfort is the only performance aspect impacted negatively by higher inflation pressure.
Really?
No negative effect on traction or tire wear?
No possibility of increased damage from pothole impacts? |
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| N_Jay |
quote:
Originally posted by xGS
What you imply is that ride comfort is the only performance aspect impacted negatively by higher inflation pressure.
In general, Yes
quote:
Originally posted by xGS
Really?
Yes, Really.
quote:
Originally posted by xGS
No negative effect on traction or tire wear?
Not with radial tires of normal widths.
You may find the center wearing slightly ahead of the edges, but as it has been explained to me, the center is wearing no faster than at lower pressures since tire ware is decreased overall with higher pressure.
Less flex, less squirm, less wear.
quote:
Originally posted by xGS
No possibility of increased damage from pothole impacts?
Its a trade off.
Impact damage can occur when the tire is either subjected to a sharp impact , or pinched against the rim.
Point pressures go up, but the chance of pinching goes down.
I doubt anyone has figured out which is more likely at what pressures for what type of driving.
I have had only one pothole caused flat in my life, and it included rim damage and a cut sidewall so I think I may have lost that tires no matter what. |
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| youbetcha |
If you inflate it to sidewall pressure would you have to make sure that it is below that pressure under all conditions?
For example, is the max sidewall pressure a "cold" tire pressure, like the doorjamb pressure? |
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| N_Jay |
quote:
Originally posted by youbetcha
If you inflate it to sidewall pressure would you have to make sure that it is below that pressure under all conditions?
For example, is the max sidewall pressure a "cold" tire pressure, like the doorjamb pressure?
The sidewall pressure IS a cold measurement and does not need to be adjusted.
http://www.tirerack.com/tires/tiret...sp#maxinflation |
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| Roger |
| I run mine at 42, no problems so far. |
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| xGS |
quote:
Originally posted by N_Jay
You may find the center wearing slightly ahead of the edges, but as it has been explained to me, the center is wearing no faster than at lower pressures since tire ware is decreased overall with higher pressure.
Less flex, less squirm, less wear.
Which tire manufacturer makes that claim?
According to Goodyear, overinflation causes uneven treadwear which results in reduced treadlife. |
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| N_Jay |
quote:
Originally posted by xGS
Which tire manufacturer makes that claim?
According to Goodyear, overinflation causes uneven treadwear which results in reduced treadlife.
No tire manufacturer, auto manufacturer, or major tire sales/installation shop will recommend anything other than the "recommended" pressure for a variety of reasons including liability.
Lets add up what we do know.
1) There is no perfect pressure, we are dealing with a large set of compromises.
2) Tire wear is due to friction, and abrasion.
3) Tire wear is hastened by heat.
4) A hard tire flexes less than a soft tire.
5) A hard tire runs cooler the a soft tire
6) The maximum inflation is usually less the 50% over the recommended inflation. (we are not discussing serious over-inflation)
7) Unless you are directly abrading the tire (skidding), I don't believe contact pressure significantly changes surface wear. (and material Scientists here to help us?) |
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| xGS |
quote:
Originally posted by N_Jay
No tire manufacturer, auto manufacturer, or major tire sales/installation shop will recommend anything other than the "recommended" pressure for a variety of reasons including liability.
Lets add up what we do know.
1) There is no perfect pressure, we are dealing with a large set of compromises.
2) Tire wear is due to friction, and abrasion.
3) Tire wear is hastened by heat.
4) A hard tire flexes less than a soft tire.
5) A hard tire runs cooler the a soft tire
6) The maximum inflation is usually less the 50% over the recommended inflation. (we are not discussing serious over-inflation)
7) Unless you are directly abrading the tire (skidding), I don't believe contact pressure significantly changes surface wear. (and material Scientists here to help us?)
7) Tire manufacturers state otherwise - what do you know that they don't?
They specifically design the casing and formulate the tread compound to achieve a uniform distribution of contact pressure across the surface of the tread, thereby improving treadwear and treadlife. Overinflation defeats that. |
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| N_Jay |
quote:
Originally posted by xGS
7) Tire manufacturers state otherwise - what do you know that they don't?
They specifically design the casing and formulate the tread compound to achieve a uniform distribution of contact pressure across the surface of the tread, thereby improving treadwear and treadlife. Overinflation defeats that.
How do you calculate the proper inflation?
Or do you just use the manufacturers recommendation?
Do you adjust for weather, load and speed?
Or do you assume that the recommendation takes all this into account and changes in tire pressure are MORE significant than changes in load, speed, and weather? |
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| youbetcha |
quote:
Originally posted by N_Jay
No tire manufacturer, auto manufacturer, or major tire sales/installation shop will recommend anything other than the "recommended" pressure for a variety of reasons including liability.
What liability are they concerned with, if comfort is the only real negative? |
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| N_Jay |
quote:
Originally posted by youbetcha
What liability are they concerned with, if comfort is the only real negative?
Oh, so you have to actually be at fault for someone to go after the corporate deep pockets?? :rolleyes: |
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| xGS |
quote:
Originally posted by N_Jay
How do you calculate the proper inflation?
Or do you just use the manufacturers recommendation?
I just use the manufacturer's recommendation.
quote:
Do you adjust for weather, load and speed?
Or do you assume that the recommendation takes all this into account and changes in tire pressure are MORE significant than changes in load, speed, and weather?
I would adjust for load and/or speed per the manufacturer's recommendation. Honda lists only one recommended pressure for the Pilot, independent of load and/or speed. On the other hand, for my Acura Legend, the normal recommended pressures are 33F/30R, with an increase to 39F/39R for a maximum load and/or very high sustained speeds.
As far as weather is concerned, increasing inflation pressure to try to reduce hydroplaning, for example, can come back to bite you with longer stopping distances caused by less tread contact - it's simply not worth it. You'd be better off choosing a tire with a tread pattern designed to provide adequate water evacuation at normal operating pressure. |
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| N_Jay |
quote:
Originally posted by xGS
I just use the manufacturer's recommendation.
A safe set of compromises.
Best comfort with acceptable handling, safety, wear and mileage.
quote:
Originally posted by xGS
I would adjust for load and/or speed per the manufacturer's recommendation. Honda lists only one recommended pressure for the Pilot, independent of load and/or speed. On the other hand, for my Acura Legend, the normal recommended pressures are 33F/30R, with an increase to 39F/39R for a maximum load and/or very high sustained speeds.
Yep, kind of interesting how the Pilot is about the first car I have ever had that did not have load and speed recommended changes.
No magic in the car, and the tire are "normal" tires, so I figure it is a "Marketing change".
quote:
Originally posted by xGS
As far as weather is concerned, increasing inflation pressure to try to reduce hydroplaning, for example, can come back to bite you with longer stopping distances caused by less tread contact - it's simply not worth it. You'd be better off choosing a tire with a tread pattern designed to provide adequate water evacuation at normal operating pressure.
Of course the supplied tires are marginal in both these areas, so You could run a better tire at higher pressure and still be in the same operating envelope, yet get batter mileage, cooler running tires, longer wear, and better handling.
OR,
You could run the same "better tires" at the same pressure and get the same ride, life, handling, mileage, with slightly improved wet braking.
Oh the natures of compromises!
You make yours, I'll make mine.
P.S. you may want to go back and read my original recommendation. ;)
EDIT: Some intyeresting reading. (For those who care to make there own compramise decisions)
http://www.nhtsa.dot.gov/cars/rules...sure/LTPW3.html
http://www.turnfast.com/tech_handling/handling_pressure
http://www.nhtsa.dot.gov/cars/rules...sure/LTPW3.html |
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| xGS |
quote:
Originally posted by N_Jay
P.S. you may want to go back and read my original recommendation. ;)
Which was:
"anywhere from 2 PSI above the door sticker to 2 PSI below the sidewall."
Let's run through an example:
Door sticker recommended pressure is 32 PSI + 2 PSI = 34 PSI.
Maximum (sidewall) pressure for the Toyo tires presently in use is 36 PSI - 2 PSI = 34 PSI.
So, according to your scheme, the pressure should be maintained between 34 PSI and 34 PSI.
Seems straightforward enough - we'll give it a try. |
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| N_Jay |
quote:
Originally posted by xGS
Which was:
"anywhere from 2 PSI above the door sticker to 2 PSI below the sidewall."
Let's run through an example:
Door sticker recommended pressure is 32 PSI + 2 PSI = 34 PSI.
Maximum (sidewall) pressure for the Toyo tires presently in use is 36 PSI - 2 PSI = 34 PSI.
So, according to your scheme, the pressure should be maintained between 34 PSI and 34 PSI.
Seems straightforward enough - we'll give it a try.
I would not buy tire with so little margin. What is the load rating?
Are they OK for the Pilot? |
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| xGS |
quote:
Originally posted by N_Jay
I would not buy tire with so little margin. What is the load rating?
Are they OK for the Pilot?
Load rating is 104 - same as for the OEM tires.
Why would they not be OK?
Perhaps you'll recall that the FMVSS were amended to permit 44 PSI maximum pressure solely for the potential benefit of higher fuel economy, without any increase in the load capacity rating.
You may want to review the "excellent explanation" in this thread:
[http://hondapilot.org/forums/showth...hp?threadid=280] |
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| N_Jay |
quote:
Originally posted by xGS
Load rating is 104 - same as for the OEM tires.
Why would they not be OK?
Perhaps you'll recall that the FMVSS were amended to permit 44 PSI maximum pressure solely for the potential benefit of higher fuel economy, without any increase in the load capacity rating.
You may want to review the "excellent explanation" in this thread:
[http://hondapilot.org/forums/showth...hp?threadid=280]
I don't think they are not "OK" if they have the appropriator load rating, just that they don't seem to have much margin in their design if the maximum pressure is so close to the standard pressure.
I have never heard (someone correctly me if they know otherwise) where a tire carries LESS load under higher pressure. (within its design range)
So, ratings aside, two tires with the same load rating at a standard pressure, the one with a higher maximum pressure most probably has more load carrying margin in its design.
Remember the ratings are just set specification points. They don't define the physics of teh situation. |
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