I have a strange tire problem......
I have a 2011 Ford Fiesta, purchased new in late February of 2011. It is the
SE Hatchback (not SFE) with Kumho Solus KH25 185/60-15 tires on alloy
wheels. For the first 5 months I added air to the tires once (and I did
check them regualrly). In late July, out of the blue, the low tire pressure
warning light came on when I was on the way to work. I was afraid I had a
tire going down, but the car drove normally so I continued on to work. As
soon as I got to work I looked at the tires and all appeared normal. When I
got home and checked, the pressure in all four tires was in the mid-20s.
Weird. I reinflated all the tires to 35 psi. All seemed fine for the next 3
weeks or so, until yesterday. The low tire pressure light illuminated on the
way to work again. As before when I looked, the tires seemed fine. As
before, when I checked the pressure, 3 of the 4 were in the mid 20s, one was
in the low 20s. I reinflated the tires to 35 again. I've had a lot of cars
and a lot of tires, and never before have I had a set of tires (four tires,
not just one) lose 10 pounds of pressure in less than a month.
Any thoughts? My only thought is that I somehow damaged the tires on a mid
July trip to Florida. We drove I-95 to South Florida in mid July. The trips
were quick (600 miles, <10 hours including stops). Is it possible I somehow
damage the tire structures in such a way that all four are now uniformly
(more or less) leaking air at a much higher rate than normal? Parts of I-95
are really rough, it was really hot, and the trip to Florida and back was
Some evening (when it's a little cooler out) after driving around for a
while until the tires are good and hot, take a small brush and brush a
liberal amount of water and dish soap solution around the bead areas and the
valve stem (both on the filler valve area and the seal at the rim) and see
if any bubbles form. It may take a little while since the leak is very slow.
I've had leaks before where the filler valve had worked loose just enough to
leak out the way you describe, but I've also seen leaks around the bead
area, but usually on older rims than you have.
LOL, no, not all four. But maybe with the extreme heat of the Florida trip,
maybe the stems loosened some? Those aren't the tires that cam on the
Fiesta, are they? Or did it come with Kumho's on it? It would be awfully
hard to prove, but maybe some damage from the installer? Still hard to make
it all four tires/rims though.
Good luck with it. Let us know whatever the resolution is.
Kumhos are the original equipment tires on 2011 SE Fiestas. The car has the
Ford valve stem attached style of pressure transducers with the replaceable
rubber valve stems. I have had the same style on two other Fords and never
had a problem with the stems or tires - but then I never drove back and
forth to Florida in 100 degree July weather with those vehicles.
The Kumho tires seem decent. At 15K they still look good, don't bump and
seem grippy enough for NC weather (little snow!). But this realtively fast
air leaking has be baffled. I guess I need to check them at least weekly
(they never have "looked" under inflated).
there's a very limited number of possible causes, so let's consider:
* tires. they're multi-layer, and there are several features designed
to help air retention. one is the bead that contacts the rim. another
is the butyl rubber liner that decreases air permeability. if either of
those have been cheapened, and if you look, you'll see those tires are
made in china, they will indeed lose pressure faster than you're used to.
* valves and valve stems. the mold seam sealing surface is crucial to
airtightness, and it's easy to screw up with a poor quality molding
machine. same for the seal bands on the valve.
* the rims. while unlikely, rims, especially cheap cast aluminum, can
you could also of course have a flat - a staple on the freeway will
explain the single "flattest" tire but still be hard to spot.
but the reason they're all losing air so fast, for my money is either
tires of valves. you can have the latter replaced cheaply enough. if
it's the tires, and it's bugging you bad enough, you'll have to replace
them. get stuff that's not made in china where they cut corners and use
unskilled labor, and you'll be fine.
The Ford warranty covers the tires. The amount covered depends on the
mileage. I am past the 12,000 mile mark (100% covered till then), but in
theory Ford will cover 60% of the cost of the tires, if the problem is the
tires (at least till I hit 24,000). And the tires may have a manufacturer's
warranty as well. But, I suppose I'll need a little more history before I
try to get Ford to do anything. I'll monitor the tires for a couple of weeks
and if they still seem to be losing pressure at an unusal rate, I'll visit
the dealer. I can't imagine this will be an easy sell, but you never know.
It's /very/ unlikely to be the tires that are leaking unless there's a
puncture. And it's even less likely to be a puncture if all four wheels are
exhibiting pressure-loss at the same time. Unless there's some kind of
obscure manufacturing-defect, of course.
Your most likely culprits are the wheels (porous alloy; poor sealing at
rims), or the valve stems (core; at hole where stem goes into wheel).
This is why you get the warranty that came with the car...
If the tires had this problem from new, I'd agree porous wheels could be the
problem, but I doubt four wheels developed similar poroisty after 10,000
miles of use. I just don't picture anything I've done with or to the car
could increase the porousity of aluminum wheels (Ford OEM).
The valve stems are a possibility. Ford uses TPM sensors that incorporate
replaceable rubber valve stems. The same sort of valve stems were used on
two other Fords I've owned and never gave a problem. It is certainly
possible that the stems are at fault, but it just seems unlikely that all
four would fail at about the same time and lead to similar leage rates. I
suppose the stress of the trip to Florida could have affect the stems but I
think it is more likely to be the tires.
I am focusing on the tires becasue I wonder if the stress of the trip to
Florida (hot temperatures, bumpy / lousy I-95 road surface, continuous
driving for 9 hours in each direction, etc.) might have damaged the inner
structure of all the tires (and since I've never had Kumho tires before, I
am suspious of them). I've checked in the Fiesta forum and no one else has
reported a similar problem. Googling leaky Kumho tires get no relevant hits,
etc. I think going back to the dealer is the samrt move, but I want to
monitor the tire pressure for a few days to confirm they are leaking at an
unusal rate. I can't imagine what the dealer will want to do to confirm
slowly leaking tires or wheels or valve stems....... But whatever, if the
problem presists, I'll get the dealer involved.
I had 4 valve stems (without TPM) fail within weeks of each other -
they just cracked and let go - all at about 15 months, give or
take.I've owned dozens of vehicles - and serviced hundreds more, with
"exactly the same valve stems" without ever having one fail (well, the
odd one on customer vehicles over the years - but none on mine) - yet
with the cheap chinese crap currently on the market i DID have ALL 4
fail in a short period of time (first one on a trip to the east coast,
second just after I got home, third in my driveway a week later - and
the forth the same day when I checked it to see if it was shot too -
just wiggled it a wee bit and the air started leaking.
Take the tires and rims off and throw them in the shallow end of the
swimming pool - and watch for a tiny stream of bubbles. Pourous
casings were a not uncommon problem not too many years ago on several
brands and models of tires - the solution was to install a Michelin
Airstop radial tube. (gee, I wonder why THEY were marketed??)
Consider the other half of my "porous wheels"comment: Poor assembly-line
technique that results in rim leaks.
Unless there's a design or assembly fault.
Can't see that being an issue unless the tires were defective. Modern
tires are extremely tough, and are highly tolerant of very significant
abuse. Tires are old technology: All the bugs were worked out ages ago.
Kumho and Hankook are excellent-quality tires. The Koreans have tires
What did Ford change for 2011? new designs? new suppliers? new plant?
new equipment? new process?
VERY good idea. Keep as accurate records as you can. Remember, engineers
will be studying your records, so you must be as precise, as organized,
and as detailed as possible.
If you can go into the dealer with substantial and credible evidence,
you will be able to help them to help you solve your problem.
And, if this is a brand-new problem, your research may even be able to
help cause a TSB to be issued. You'll be famous!
You may even discover...Devil's advocate speaking here...that your
original thesis is incorrect, and that the tires are not actually losing
any air at all...
You never really know, until you have extensive and accurate records to
It involves water. But wonder not: This is their problem, not yours. If
Ford is the conscientious automaker they wish buyers to think they are,
their engineering staff will have developed numerous techniques to find
Some automakers are wonderfully anal about detecting and correcting
faults. You'd hope Ford is one of those.
You paid for that warranty as part of the purchase price of your car.
Time to start collecting on what you paid.
theoretically, but manufacturing integrity is just as susceptible to
"economies" as it ever was. thinning/omitting the air liner saves
money, regardless of "old" or "new" technology.
label engineering and marketing. look at the tire walls for country of
origin - most are made in china.
frod is right behind bmw in terms of their relentless pursuit of
production and design objectives and quality control. however, the
targets they so carefully and rigorously meet are not those you would
life limitation is, and has for many years, been the hold grail - their
largest r&d spend by a considerable margin. it's cheap and easy to make
reliable stuff. it's cheap and easy to make unreliable stuff. it's
very hard to make cheap stuff that's reliable only for its design
period, then reliably and predictably fail. in terms of engineering
challenge, this is probably the only thing about the industry that's got
any real intellectual horsepower behind it. getting stuff to work?
that's century old news.
Correct - the Korean Kumho tires are decent to good. The chinese
decent to CRAP.
The experience I had with Hankook tires a few years ago soured me on
even their Korean tires. Apparently they have gotten better - the ones
I had experience with had "corners" on them instead of being round -
if you know what I mean.
I won't TOUCH a chinese tire. Perhaps Taiwanese, but never mainland
china - and I'm not partial to VietNamese or Philipino tires either.
The Red Chinese produce quality work provided the West (or a free country
like South Korea) does their design and QC for them.
I've had Hankooks for the last several years. They have been, and remain,
Of course, mine have been competently mounted, something you can't say for
95% of tires out there...
Poor mounting technique. So distressingly common. It wasn't the tires,
If they're being sold under a major brand, they're fine. The point of
branding is to assure your clients that the final product is good,
regardless of where made.
Tires, and people's rate of satisfaction with them, are 100% tied to
competent mounting. But, unfortunately, competent mounting is extremely
Few tires are bad, but most tires are badly mounted. And the tires get
i know you don't like people disagreeing with you dude, but i have to
take issue on this. tire quality is very much at issue here, and it
can't be solved by "mounting".
example: when a tire casing is made, the fibers used have to be of
sufficient quality, laid right, and with even tension. same for the
tread bands - the circumferential nylon and steel layers. now we come
to the rubbers - these are obviously critical. incorrectly formulated,
poorly mixed, incorrectly applied and inadequately vulcanized, these,
just like all the other individual components, are critical quality
concerns. iow, there are many different components and processes that
can get screwed up by poor material quality assembled by unskilled labor
but even all those don't hold a candle to the #1 cause of chinese
product problems: corner cutting. if a company is outsourcing to china,
they're doing so for economic reasons, not technical. and they want to
minimize costs. so how does a chinese manufacturer manage to produce
something for seemingly the same cost or even /less/ than the open
market cost of materials and energy input? cut corners and reduce those
input costs that nobody else dare do! because let's face it - are you
/really/ going to try to file a lawsuit against a chinese contractor in
a chinese court of law? if you're entertaining the idea that you could,
you'd better see a psychiatrist for the delusional fantasies you're
bottom line: don't buy chinese tires. ever since the usa started to
allow chinese tire imports, [and also relax the rules on the tire
quality that you can have on a big rig's trailer - because chinese tires
couldn't meet quality standards any other way] our freeways have been
strewn with outrageous quantities of blown tire debris. it's an
absolute scandal. do /you/ want to be hit with 5lb, 10lb or even 30lb
chunks of tire casing from these things as they disintegrate? i had one
of my door mirrors knocked off by one recently. i'm lucky it didn't
come through my windshield or hit my elbow that happened to be in my
open window. [big thick chunks of rubber like that don't bounce btw -
they're like chunks of flying concrete.]
Who said that? Disagree all you want. There's nothing I can do either way.
It can, and it does. I have abundant personal experience with this, as I've
stated and detailed numerous times.
Most tires judged as defective actually suffer from bad mounting technique.
Most wheels judged as "bent" are actually within spec, but are declared
"bent" by tire monkeys who are stumped as to why they can't make vibrations
There's nothing at all wrong with Chinese product sold under major brand-
then you've been outstandingly lucky and have not had to witness abysmal
tire quality with visibly lumpy side walls, visibly lumpy treads, rubber
cracking and spalling, etc.
sub-standard materials, unskilled labor and corner cutting affect
quality. that's just fact. and you don't manufacture in china so you
can save on labor but spend more on materials quality, you do it so you
can cut costs all across the board. that's just fact too.
And I will dissagree with you - from MY experience - on both the tire
and the rim. Just because a rim is "within manufacturers tolerance"
does NOT mean it is not "bent", and no matter how you mount a "turd"
it's still a "turd". Can't make a silk purse out of a sow's ear.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.