FrancoP

Dear Membership,

I just made my first Lexus purchase, an '07 SC 430 Certified. It has 34k miles on it, single owner. The car is equipped with run-flats. I come from a long line of BMW's, mostly M3's, and an older 7 series. My other car is a Maserati Coupe.

There is much to like in a top-of-the-line Lexus product like this. Build quality, design, fit and finish, seamless power delivery, anticipated reliability, etc.

But this car handles kinda funny

I find that even moderate bumps cause a shudder, which can be felt in the steering wheel. The car tracks super true when going straight and on smooth surfaces. Not a vibration to be felt. But even low speed moderate bumps-particularly multiple bumps in a row-cause a shudder or springiness that I'm not familiar with. Is this normal for a stock car?

I also noticed that when entering a broad turn on an interstate on-ramp this afternoon, when the car experienced a bump while turning and accelerating, the trajectory changed and a steering correction was required. Is this normal?

As mentioned, it's a certified car, and like most who post on a forum, I need to sort out any new acquisition before I can start enjoying the car. I can't help but feel something is wrong in the front end. As beautifully engineered as these cars are, I can't imagine this is what Lexus had in mind as far as ride and handling are concerned.

I'm going to have the car aligned just for my piece of mind. I'm wondering if I have a bad shock. But with such little mileage, is that a likely point of failure.


Thanks for your insight!

Franco P
Naples, FL

OBP

Do you have runflat tires on your car ? If you do, some of what you are experiencing could be typical of RFTs. I have found bumps harsher feeling in this car than on many others. I also experience tramlining now and then. People who have switched out of RFTs to regulars have fewer complaints.

On shocks, I had both my rear shocks replaced under CPO warranty, one at about 26,000 miles and another at about 38,000 miles.

I've also got less negative camber on my car than the way Lexus usually sells them - helps me with tire wear - less uneven. I lose a little bit of handling but I'm OK with that. It's just a daily driver. If you're getting an alignment done, might want to consider if you want the camber looked at as well.

Good luck and congrats on your purchase - after you understand the SC430's idiosyncrasies, it's a truly satisfying convertible.

Harold57

The RFTs start tracking grooves real bad when they are worn but if you just purchased the car certified, the tires are probably new. (If they aren't new, the worn tires could very well be the problem.)

Poqman

FrancoP, welcome to the forum. I'd have to agree with you. I bought an '02 model and my main complaint was the shutter in the steering on the highway, especially when a series of small bumps were encountered. It felt like the car could become unstable or lose control. Not very good symptoms for a luxury cruiser. So here's what I did. 1. get rid of the rft's, 2. installed a set of coilover's, and 3. replaced the steering rack bushing's. I finally feel I control the steering. Unfortunately, I doubt your warranty is going to do any of this for you. At best they may replace the shocks as a good will act. Oh, and btw, the symptoms are worse with the top down. Body flex is worse than I expected for this car.

76210Guy

Welcome to the asylum! I too have a CPO '07. When I drove it home the first day I thought the same thing about the ride you are experiencing. I got rid of the RFTs and haven't looked back since. The car is still a little "jittery" with the top down IMHO.

Even though I've owned Benzes and BMWs, this is my favorite car to date.

Enjoy the camaraderie of the forum. These guys are a veritable fountain of intelligentsia on the SC.

robertrios

iTrader: (11)

yea its worth the investment to switch to non RFT, also I have staggared wheels which help a tiny bit with RWD cars. Next step for me is coilovers and a brake upgrade. If they still made sway bars for these cars I would definately get those as well. The handle comperable to say an M3 in the Lexus family would be a 2IS with the sport or x package suspension which can be improved with the Fsport shocks/springs.

I own and IS as well as an SC and its night and day but slowly im catching the SC up.

raywest

Hey Franco,

I had the same problem and the same 07 SC as you with 40,000 miles certified. I believe it is the run flat tires that everyone is saying because I made a post as this some days ago. The ride was super harsh traveling for 4 hours going 65-80 mph, and now my headlights need to be adjusted because the leveling is way off due to the bumps on the road. I'm planning to get regular tires, but not after I have worn out these like-new RFTs first (I don't want to waste $$$!). The best suggestion that I can give you is to slow down on these bumpy roads and hopefully you'll enjoy the ride more!

You'll love the SC despite this....I hope!

Cheers!

iolmaster

iTrader: (1)

Get rid of the run-flats. I have an 06 and got rid of mine right away. It is like a different car. I have a friend that has a 7 series BMW that felt the same way about his car until he got rid of the run-flats. If you never had run-flats this is all new to you. This is not a unique discussion with the SC. I have heard the same complaints especially from BMW owners.

tentoys

put some coilovers on and set the damper stiffer than it is stock. makes a world of difference in handling.

FrancoP

Thanks for all the replies. I too have had issues with run flats, most recently on a Mini Cooper. In any event, I will let them wear down a bit, then go back to what I think is one of the best tires ever, the Michelin Pilot line.

As for coil overs, I'm not looking to track this car. I do wish it was damped more like a 3 series than a Cadillac. If I want to preserve the luxury coupe role of this car, but want to improve ride and handling, are coil overs still the ticket? I see much written about Megan coil overs. Would a strut tower brace help matters?

On an unrelated subject, the clock is not holding time. Is there a secondary battery for holding various memory settings?

Thanks, again.

Franco

aquanuke

Would be quicker to ask who does have RFT. Mine where changed first day.

piclkeball

What are coil overs and how much do they cost. Have same problem with my 2005 with 49K. I even changed after market wheels with after market Lumarai's which are made to specific Lexus standards. Also swithched from RF's to Yokohama 580's. Better but not good.
Thanks for the help.

aquanuke

http://en.wikipedia.org/wiki/Coilover

dpspider

I had a same experience when I got my 07 SC430 last November. I was so afraid to go over even a small bumps because it vibrated so much. It made me wonder how all those SC430 owners cope with all the shudder and vibrations. I was not expecting this from Lexus. By the way it was my 1st Lexus. And I had a big expectation from Lexus's ride quality-quite and comforts. I have bought many cars before ,but I never had buyer's remorse after drive home from dealer. But it started wear off on me. I do not feel the shudder and vibration as much as before. I took her a weekend trip to central coasts,California last month and it was a blast. The ride quality is way better than MB SLK350 I had before. I hope you too will feel the same way. And enjoy her!

bacardi

welcome to the forum
you will see a big difference it you get rid of run-flat.