Toyota: Sienna Run Flat tires

Gary wrote:
 
Special eqipment is needed, they are very spendy and notr sure if a
regular tire cam be mounted on a run flat rim, in fact, I'm betting the
rim isnt different. Now how will 3 run flats behave with one
conventional tire, not sure. I suppose you could carry a spare, but the
rear well area wont take the seats in flip dowm mode and if you go with
a FWD, you can have a space saver spare, the run flat is for AWD only.

Not to mention the firmer rubber used in runflats would give the vehicle a
hard ride from what I have read.

"Philip®" <net> wrote in message
news:yJB3b.8810$news.pas.earthlink.net... 

"Gary" <net> wrote in message news:<8ry3b.7940$starband.net>... 

I've got the runflats on an AWD Sienna. Comments:

They ride rather stiffly but smoothly compared to other (non-runflat)
tires I've had, on other vehicles.

That is, small bumps, pavement cracks, ripples, etc. feel more
pronounced with these tires.

But this is the smooooooooothest riding vehicle I've ever had:
Absolutely zero discernible tire/wheel/drivetrain vibration at all
speeds up to 85mph (the highest I've had it so far). (The
RX330-common drivetrain probably helps, too...

The stiffer small bump telegraphing is a result of the stiffer runflat
tire construction, I'm sure. The super-smooth ride aspect may also
partly result from that, but a sure factor is the angular
match-mounting done by Toyota with these tire/wheel assemblies to
minimize total Radial Force Variation (RFV)- the angular alignment
marks are still visible. I haven't measured net runout or RFV myself,
obviously (no need!), but I'd bet a dollar that these tire/wheel
assemblies are on the low end of RFV and runout measureable on
production equipment. (Anyone at Hunter Engineering reading this?)

I read somewhere that the AWD Sienna suspension was tuned specifically
for the runflats, to soften it in compensation for the stiffer tires.
Haven't driven a FWD 04 Sienna with non-runflats enough to offer a
comparison, but the AWD with runflats is not what I'd call
"soft-riding" at all. It rides like a Honda sedan I remember, except
the small bumps make themselves known more (and except for the
noticeably increased mass and higher CG & lean, of course).

[Somewhat OT: The excellent drivers seat, including superb lumbar
support, soothes any visceral reaction to the "roadbumps dance", and
makes life driving an AWD quite pleasant nonetheless, even for the
over-30 crowd, imo. ]

Other:

The runflats have a treadwear rating of only 240, so don't expect long
life from them. OEM tires usually have low-ish treadwear ratings
anyway, but unlike conventional tires, replacement runflats probably
limit your options to likewise low-treadware-rated tires, so this may
increase total tire costs over the life of the vehicle significantly
due to more-frequent replacements. (If the runflat replacement market
remains very small, the runflat makers may have little incentive to
improve this...) By comparison, the Michelins I put on my other
vehicle last year have a treadwear rating of 700...sniff.

Don't know yet about special equipment required to mount runflats, but
I already look forward to a challenge anyway finding a tire dealer
with tires I want at fair price and with mounting & balancing
equipment I seek, for ANY tires I buy, because I will always demand
RFV match-mounting in the future for ANY tire I buy, so this is not
any additional hassle for me personally. (Had a recent experience
with a Hunter GSP9700 "Road Force" match-mounting/balancing machine to
cure a RFV vibration problem on another vehicle, and IT WORKS! I'm
sold!)

Not sure runflats are designed to be repaired per se, but even if they
are, I'm not sure I would trust anyone (outside of the tire maker
themselves) to do a repair. (I used to do tire service & repair, so I
know intimately the skills & workmanship variations to be found in
repair shops...)

As to the idea of replacing the runflats with conventional tires: I
believe the wheels are the same 17" wheels offered with non-runflat
FWD 04 Sienna Limited and also as an option on other trim levels, but
a trip to the dealer might confirm this. You could put a spare in the
rear well (a Dealer option?), or (my favorite idea), lashed down on
top of the roof rack, a la Outback Safari. But there is a
possibility that softer-riding conventional tires might not agree too
well with the AWD Sienna suspension tuning - this would make a large
change in tire response, to be sure.

Good Luck!

Bob H. wrote:
 

Really? I've noted 420+ treadwear ratings on most Toyota OE tires.
I would not want a 700 tire ... but that depends on the tread dept /
rubber compond used to arrive at that ratings.

--

~~Philip

"Never let school interfere
with your education - Mark Twain"

I like the idea of the run flats for most 

I hope your experience with driving an '04 Sienna on gravel roads is more
positive than mine. For the first several thousand miles I would have given it
an A rating with respect to body integrity (rattles, creaks, etc.). Then I
drove maybe 20 miles on forest service roads around Flagstaff. Now it's an F!
Creaks like crazy around the sliding doors.

Otherwise, a decent vehicle, BTW. Went cross-country without any back pain,
which is unusual for me and speaks well for the driver's seat. Wish it had
less body roll when cornering (recollection from test drive is that the Odyssey
handled better). Very good drivetrain: I don't like automatics but this one
is at least pretty responsive.

By the way, I decided to NOT go with AWD because of the run-flats. Whatcha
gonna go with a flat in Blanding, Utah, for example? I understand that a flat
isn't likely but who needs the hassle if you get one?

Tom in PA

A few thoughts and questions:

Actually, there are two tire dealers in Blanding, Utah (Bradford Tire and
Canyonlands Tire). I don't know if either of them stocks the Sienna
run-flat tires, though, or has any Hunter equipment....

I think that if I wanted to do very much exploring in this neck of the
woods--say, on the Navaho reservation, I'd want to have a spare tire. Even
if I had to carry it on the roof. But, hey...this is a family car, not an
ATV.

According to Bridgestone, the run-flats are mounted on conventional rims:

http://www.bridgestone-firestone.com/news/consumer/2003/030305a.html

So, the question arises, why could one not just put some other 17" tire on
one's rims? Matching them, to be sure. And are the OEM Bridgestones so
good that they render the question of snowtires academic? One thing for
sure is these puppies are expensive.

Also, does the presence of a TPMS (tire pressure monitoring system) enter
into the argument? Slow leaks not sneaking up on you, that sort of thing?

I would hate to tempt the fates, so I'll knock wood three times, but the
last time I had a flat tire was in 1973. Lucky? Careful? Both? And as I
drive, it seems to me more often than not, that when I see some poor soul at
the side of the road with tire trouble, it is as the result of a blowout.
You can't "run flat" on a blown tire, can you (except on "World's Stupidest
Car Chases")? Or are these tires immune?

Did you ever get your sliding doors to stop rattling? Is the door opening
so big that it's extra easy to twist the monocoque? ;-)

"Vmcw" <com> wrote in message
news:aol.com... 
be 
given it 
I 
an F! 
pain, 
had 
Odyssey 
one 
Whatcha 
flat 

>A few thoughts and questions: 

Good to know! I assume you get my point though: you're probably in for more
hassle and expense if your run-flats fail in the hinterlands than if you're
running regular tires. And you're in for a HUGH hassle if one self-destructs
to the point of not being driveable in the middle of nowhere. 

 

They're still creaking at the moment. I haven't taken it into the dealer for
this yet, as I've been waiting on parts for my recall fuel tank repair. Wanted
to try & get it all done in one visit (as if that ever happens). Based on
previous experience with dealers finding creaks & rattles, I'm not real
optimistic about the outcome.

So what's a monocoque?

Tom in PA


(My original post follows if anybody cares...... or even if you don't!)

 

"Nemo Oudeheis" <net> wrote in message news:<Jx94b.11605$news.adelphia.net>... 

Nowadays, good radial tires are much less prone to blowouts than the
old bias ply tires were, pre-70s. Next time you see a blowout, take a
close look - I'll bet the tire was running bald and/or very low
pressure, leading to a puncture, or tread separation, and/or
overheating >>> blowout. Steel belted radial tires at proper pressure
& with nice thick tread are cooler running and less susceptible to
puncture damage, better warding off the 2 main contributors to blowout
- heat and mechanical damage.

How many times a year do you see someone with a flat tire on the side
of the road, anymore? I haven't seen one in quite a while.
 

Would depend on how severely it's "blown". If there's enough sidewall
to run on, then, "run on, dude!". These runflats are the type
with reinforced sidewalls, (a) so I would assume that they can be used
- limping at least - without air pressure even if there is some
limited sidewall damage - but you're on your own in that case, which
is really the case anyway, isn't it?, and (b) I would expect the
stouter sidewalls to be more resistant to damage in the first place,
compared to conventional tires. 
<snip>

Hmmmm..all this talk of $$$ and hard to find runflats...I think I'll
start looking into that roof rack mounting for a spare...next I'll
shop around for brush guards and a snorkel intake, then we can start
checking out the guided safaris for a coming vacation.