Tires: tire pressure, tire placard, goodyear fortera

Question
QUESTION: I bought the fortera tripletread tires. Ihave a ford explorer limited, on the door the pressure says 32 pds. I seem to lost about 2 to 3 mpg. Ive looked for the correct pressure on the interent , it seems everybody has different pressures. Could you please help... thanks don

ANSWER: Don,

If the tire size listed on the door placard is the same as what is on the vehicle, then the pressure also listed there is appropriate.

If the tire size is different, then post both the tire size and pressure listed on the placard, as well as the size that is currently on the vehicle, and I will recalculate the pressure.  the starting point for the calculation is the door placard, so that info is important.

---------- FOLLOW-UP ----------

QUESTION: thanks for taking time to help. the door panel reads ,235/65/r18 .the pressure says 32psi which i have in tires now. on the tire it say max. pressure 44psi. i also have 235/65/r18 on the car now. i have a 2007 ford explorer limited. thanks again......don  

Answer
Don,

OK, so you have the exact size as listed on the tire placard, so the pressure listed there would apply - 32 psi.

But your real question is:  "Why did I lose some fuel economy?"

1)  All other things being equal, new tires will consume more fuel then wornout tires.  This is because there is more material in the tread area being flexed as the tire rolls.

2)  OE tires will generally have better fuel economy than tires designed exclusively for the replacement market.  That is because treadwear, traction, and fuel economy are tradeoffs for tread rubber compounds.  That is, if you find a tire with very high treadwear ratings, it is because something else (traction and/or fuel economy)has been sacrificed.  In your case, the Goodyear Fortera TripleTread was designed in an era where treadwear was about the only thing important to the consumer.  It has a very high 600 UTQG treadwear rating - and by inference it will not be good for fuel economy.

If you want more details about this, visit my website:

http://www.barrystiretech.com/