Cruizing

I know the majority feels the runflats are terrible (commonly referred to as "runcraps" )and have replaced the tires with conventional tires. I also know that many have increased the wheel size to 19's or more commonly 20's. I know many of the Vettes, BMW, and Vipers are now using runflats. My question is has anyone tried a different manufacturer of runflats than stock? Michelin Pilot Sports A/S have ZP runflats in 275/40YR18 (limited sizes alvailable). Before I take my anti-pychotic meds and be quiet I just wanted to ask.

tfischer

I would disagree with "majority" and "terrible."

There have been a lot of posts here from owners who are not happy with the ride on the runflats, but I doubt that most of us consider the ride terrible. The ride, obviously, gets softer if you substitute a tire with a softer sidewal and higher profile . Everybody that has done so has reported an improved ride, which is to be expected.

For my part, even after reading the posts, and after 4 years of driving the car, I have not felt moved to change the tires, even though the ride would be improved. For my part, I am not crazy, after some previous flat tire in the boondocks experiences, about not having a spare or, in the alternative, of filling up the trunk with a spare. I accept the compromises.

When the time comes to replace the tires, I will look for the best runflats available in that size at that time, (I have heard that the Michelin is an improvement over what Lexus has been using as original equipment) but the cost and the disadvantages of non-runflats is not something I am interested in.

Nobody wants to generalize from insufficient data, but it's my guess that only a small percentage of SC430 owners have traded out the runflats for other tires.

If you feel the ride is "terrible," by all means try something else, but it's a matter of personal predelictions and your level of risk tollerance.

ron36330

The secret to the run-flat tires is to INCREASE tire pressure. I use 38 psi (cold) as per the Lexus TSB which I have quoted elsewhere in this forum. In any event the ride is greatly improved and you will no longer notice small imperfections in the pavement. However you still get a jarring ride over large potholes, RR tracks ,etc. None the less increased tire pressure allows you to retain the convenience and safety of run-flats.
Ron

tfischer

I have been running them at 40 for the past year or so, and, as mentioned, I don't think the ride is all that bad at all.

I've taken many long trips in the car, and expressway driving is generally pretty smooth, but even around town it's only the occasional big bump in the road that gets noticed, and I can live with that.

rominl

iTrader: (4)

umm that's very interresting, why more pressure will actually make it better?

i definitely don't like the runflats on my car. i can live with it, but if i know i am NOT getting any aftermarket wheels for a long time, i would haev changed them out

Cruizing

Perhaps the extra pressure rounds up the tire taking weight off the outer edges. This might reduce the tramlining that is normally present in uneven roads as the outer edge tries to climb up the ruts. Obviously it won't help with the potholes. On cornering the stiffer walls should help prevent the tire from rolling and thus shouldn't affect the cornering.

rominl

iTrader: (4)

interesting theory, that might be the case.

lexuslover

i got the 15k service on the SC last week; tech told me that my tires should have been pumped up to 40psi (mine were at 28 for some reason ). i did notice a change on the freeway, although it's the bumps that are really rougher.

i haven't changed the oem runflats yet, but i plan to once they wear out. should i try the michelins? how much tread life do the runflats get ? mine look ok so far, but i am guessing i will have to change them once during my 45k lease, so might as well do it half-way through...

rominl

iTrader: (4)

at 28psi the flat warning light didnt' come on? at what psi would it?

tfischer

Before I started running them at 40, the warning light came on once or twice, probably at about 20 or 22.

I have 20,000 miles on the original tires, which have been rotated at least 4 times, and they look to have 3 or 4,000 more miles left on them. Original estimates were as low as 10,000, but the tires were a new type, and of course, the manner of driving and frequency of rotation have a lot to do with that.

One other note for those looking at new wheels: most replacement wheels will not take the tire pressure sensors, or will only do so at some considerable extra cost. While you may not miss them, especially if you are going to tote around a spare, without the sensors, the warning light stays on and seems to be a bit of an annoyance. Search for posts about this to get the full story and a few solutions and work-arounds.

XZLR8

I didn't think the OEMs were great until I swapped them out for winter Blizzak runflats. Now that the OEMs are back on for spring, I have a new-found appreciation for them. Those Blizzaks were truly awful.

But I agree with earlier posts. I'm just not ready to go w/out a spare.

robshippy

After 19,700 miles, I replaced the factory runflats [back in October '04].

Based solely on feedback from SC430 owners whom have posted recommendations in this forum, I went with the Michelin Pilot Sport A/S.

What a difference these tires make! The ride is so different (and better), that I wish I would have replaced the factory runflats 19,700 miles ago [when the car was new].

I would reccomend to anybody that replacing the runflats with conventional tires is totally worth the risk [of driving without a spare]. The ride is much better than when the car was brand new and I think it makes the SC430 "ride" almost as nice as the LS430.

-Rob S.

lexuslover

Hi Rob S -

good to know about the michelins; so i am guessing you have not had the problem with the low pressure sensors coming on with those tires? and how does the cost of those stack up against the OEM bridgestones? thanks for your help!

and rominl, i was a little shocked to find out that i was at 28psi with no warning light, but to tell you the truth the tires always *looked* properly inflated, never a sag or overinflated center. i guess the RFs can be deceptive. i guess i will have to bust out the tire gauge every once in a while

rominl

iTrader: (4)

yeah the rf they look the same all the time, even without any pressure

somehow i thought anything under 30 it's going to trigger the sensor. guess it has to be lower

Cruizing

If I remember right it is about 22 psi that the sensor goes off. It happened to me this last winter when it got cold. Il will have to try over inflating the tires to try the ride. Obviously on good pavement the runflats are beautiful. I still wonder what the Pilot runflats are like.