On 1/6/2016 7:18 AM, Wade Garrett wrote:
On 1/5/16 10:06 PM, Don Y wrote:
On 1/5/2016 6:43 PM, Ed Pawlowski wrote:
Newer cars have a TPMS and warn you when the pressure gets low. Now
that cold
weather is here,check to see that your tire is at least the recommended
pressure. I forgot about it and this morning it was 7 degrees. One
tire was 1
pound under and set off the warning. It would not reset after driving
as it had
to come up even more than driving did. Filled it up when I got home.

Not a major deal as I knew the pressure was adequate to drive, but it
annoys me
to have that yellow light on when driving. I understand this is a common
happening for the first really cold snap.

We're back at Costco every week or two having them add nitrogen to
the tires. On a cool day (30-ish in the AM), tire pressure (all
around) will be low. However, on a warm/normal day (80-ish in the PM),
pressures will be high -- TOO high if we'd added nitrogen on one of
those colder mornings!

[I think it's 1 psi per 10 degrees F?]

And, the Costco tire droids want to "overfill" by ~3 psi claiming
the tires are "hot" now that you've driven on them. So, instead
of 35/33 psi, they'll fill to 38/36 psi. Then, the ambient
temperature climbs 40 or 50 degrees and the tires are considerably
overinflated.

So, bleed out some nitrogen to bring them down to ~40/38 ("hot")
and hope we don't get another cold day to bring them *down*, too far.

Filling tires with nitrogen rather than old plain air (78% nitrogen anyway) is
one of those things that sounds good on paper and which tire buffs rave about--
but which has little impact in the real world.

Plus I suspect it costs you more in gas to drive over to Costco than you
actually save. You also have to let some lead-foot 85 IQ tire installer jerk
drive your car while you sit around on a ripped vinyl chair in an uncomfortable
waiting room-- or worse, roam around the store and pick up a shrink wrapped
pack of 96 rolls of toilet paper or a 5 pound box of corn flakes...

We can drive the 2 miles to Costco to have *them* put 95% N2 in the tires.

Or, we can drive the 2 miles to the Albertson's ACROSS THE STREET from Costco
and drop quarters into the *air* dispenser and fill the tires ourselves.

Or, we can buy a small compressor and find a place to store it for the
few times it's needed.

Given that we shop *at* Costco every week, there's no cost to having them
do this -- other than waiting 60-120 seconds for the tire monkey to drop
what he's doing and walk over to the car (WHILE WE SIT IN IT) to do this
for us.

[BTW, there are only 30 rolls of paper in the packages and neither of us
eats Corn Flakes]

Have you actually ever *been* to a Costco? Or, are the ones in your part
of the world NOT as friendly as ours?