kgmobley

dseag2, we are not getting poor performance from the Dunlops. The ride has improved about 50% over the OEM Bridgestones runflats. My wife is really happy with the ride; she has commented a couple of times from both the drivers and passenger seat how much the ride has improved.

Prior to getting the tires, I was not sure how much the ride would improve. The posts on this forum and on Edmund suggested a lot (100%, 200$, night and day......) if I switched out to either the 2nd generation runflats or to non-runflats. The first night we had the tires changed, I jumped in the car with really high expectations. What I found was not a night and day difference, but a significant improvement in the ride. With the new Dunlops, there is very little feedback from small to medium road irregularities. With large irregularities (pot holes, large bumps in the road, bridge separations, etc.) the car transmits a short dull thump into the cabin--as much as we to miss them, we have to stay in one lane and some times these road conditions are unavoidable.

As a GT car, I look at the car's ride as different from that of an cushy vehicle (over past couple of weeks I drove a friends Ford Ranger truck over the same road irregularities and the truck transmitted less into the cabin when it hit the potholes and humps in the road--the little truck just bounced over the potholes). This is an extreme comparison, but I am using it to illustrate a point that the suspension on the truck is vastly different than on the SC. The SC transmits a little more road feel into the cabin, but it handles 1000% better than the Ranger--I would never take Ranger into a turn at 140 plus, as I have done with the SC (on a closed track).

Kevin

dseag2

I'm glad to hear the Dunlops are significantly better. I used to cringe when I knew an unavoidable bump in the road was ahead.

FYI, I understand the difference between the SC suspension and that of a truck. I also understand that the ride doesn't have to be rough for the car to have competent handling... GT car or not. The ride in my GS300 is pretty darn smooth, and it has L-tuned shocks and springs. The shocks are stiffer than stock and the springs lower the car by 1". As a result, the handling is amazing. However, the ride hasn't suffered.

That leads me to believe that a trade-off doesn't have to exist between ride and handling. Three other SC430 owners who just posted have also verified that. I wasn't criticizing your decision to go with the Dunlops... just pointing out that you don't have to sacrifice. Glad you've seen an improvement.

kgmobley

Thanks. With the tires behind me I have other two other concerns.

The noises and rattles. I heard two different ones this morning, one outside the driver door and the other from the rear passenger side. I have had Lexus add padding to eliminate the rattles in the past, but new ones seem to come up. I have long suspected that the old run-flats were transmitting some much vibration into the cabin that things were coming loose.

The other concern that I have is the hum from the door cranking up the sound system.

Six months ago, there were a lot of posts about these problems. I wonder with the switch out to newer runflats and the non-runflats, if the rattles have subsided for other SC owners.

Best regards,

Kevin

JCtx

My car also developed 2 rattles in its 750 mile life. One was driving me nuts, and seemed to emanate from the left rear headrest area. After realizing I could reach while driving (although weaving a little -he he), I started poking everywhere with no success. Then I realized it must have been coming from the trunk; and it did. It was the plastic cover that goes over the main pivoting mechanism; just tweaked it and the rattle went away. I have the feeling it'll come back when I open the top again, at which time I'd remove the darn piece and find a more permanent solution. The right one is very solidly attached. At any rate, this would be very easy to fix by myself. this rattle was driving me nuts, so 'good riddance'.
The other, however, is more elusive, but less annoying. It was coming and going, and apparently came from the bottom of the right side of the right front seat; started poking around, and for now is gone, so I know it's superficial.
I noticed the latter started after I hit an abrupt (raised) bridge expansion that run about 30º from across the street, which jolted the car badly, with the accompanying creaking noises. I'm sure it was like an inch higher, but felt like a foot. Boy, I hate ultra-low profile tires (and worse in RF version) in these cases.

And yes, I hate rattles with a passion, but remember on a car so quiet, you can hear almost anything. Also remember a convertible has a ton of moving parts, which makes it harder to achieve a quiet car. I'm impressed with how quiet this car is, compared to my BMW convertible, or to any other car for that matter. I won't make excuses for Lexus, but I expect a rattle or two to be permanent on a convertible. So far the car is 'exceeding my expectations' in that department. Even for a perfectionist like me, I know nothing is perfect, so I don't expect anything to be perfect (although I pursue that), or I'd go nuts.

Take care guys.

JC

kgmobley

Yeah I agree. I think all of us on this board are perfectionist. We drive the service technicians at Lexus crazy.

Has anyone had their car doors reinforced to stop the hum when the sound system is turned up?

Kevin

Bobs SC

Got my michelins today and it is night and day compared to the runflats Such a smooth ride the way a lexus should have felt to begin with. The shop I took it to though broke one of the sensors so now they are ordering a new sensor for me and putting it on monday. Geez that beeping noise is annoying as hell.

JCtx

Hey KG, found the culprit on the seat rattle: the stupid seatbelt buckle. In its normal resting position, it was banging against the hard plastic on the seat's side. Raised the buckle and lodged it against the seat, so it should be whisper quiet again. I hope it stays that way. Sometimes I like to drive without the stereo on, and now I can enjoy that again.

Hey Bob, what pressure are you using? Good to hear about your results.

Another piece of information. Just read the new C6 vette has newly developed Goodyear runflat tires (3rd gen) that are even good in snow, and much quieter than before. The better news is their front tire size is identical to ours: 245/40/18. One more choice people.

I'm going on a skiing vacation shortly, so I'll leave you guys alone for a few days <he he>. Take care.

JC

Doc C

Bob,

Glad to hear you like the tires. I figured you would. A lot of people on here that are pro runflat tire have not had the comparison of the non RF vs. the RF. I haven't been on here long, but I have yet to hear one person post that they got Michelin Pilot Sports, or Goodyear F1, or any other non RF tire after having the Rfs and say that they wished they had their run flat tires back. I'm probably wrong, but I don't think I'm wrong to say that the vast majority of them have always liked the non run flats WAY better. To get rid of the beeping you can just unplug the little wire under the steering wheel in the driver's side footwell until you get your sensor back. See the FAQ area of the forum for better instructions. Good luck!!

Doc C

Bobs SC

Doc,

Thank you for that info. What are you using for a spare tire? I think I am just going to take my chances. I used to have a mercedes slk with no spare and I survived.

Doc C

Bob,

I think I'm going to get a temporary spare for long trips. Lexus wants a LOT of money for them though. I'm going to check at some salvage yards because I'll bet there are plenty of those in wrecked vehicles that haven't been used. Otherwise, Lexus roadside assistance is the other alternative.

Doc C