neilsarkar

I leased a (non F-Sport) '15 GS about four months ago. Loving the GS so far except for one thing - the highway ride is rather busy and noisy, which does not at all suit the character of this car. I specifically avoided F-Sport package because I wanted a luxury car ride. My previous car, BMW 535i, had way quieter and smoother ride in spite of having run-flats. Go figure.

Do you think I can get meaningful improvement by upgrading the OEM tires? The GS came with Bridgestore Turanza ER33. I'm thinking about replacing them with Pirelli Cinturato P7 All Season Plus, which gets a lot of praise in Clublexus. Please let me know your opinions.

ryanSC300lover

iTrader: (1)

Mr. Sarkar ,

Check out this thread
https://www.clublexus.com/forums/gs-...py-ride-2.html

I have 3 cars in the garage with Michelin premacy which I am a believer in. I have one car with Pirelli p7 (LS). Pirelli is super smooth and quiet

Premacy is quiet as well but if you are looking for quiet soft pillowy ride I would say go with p7

Good luck

peteharvey

I compared my 2015 Luxury with my friend's 2013 Luxury back to back, and I found that his original 2013 4GS was softer somehow?
I asked Lexus if the 2015 Luxuries had upgraded suspension compared to the original 2013 4GS Luxury.
Lexus asked me to supply them with by my 2015 chassis number, and my friend's 2013 chassis number.

After analysis, the Lexus parts depo told me that my 2015 4GS Luxury actually got the F Sport's front coil springs, the F Sport's front dampers, and a silver version of the F Sport's 19" alloys!
The rest of the 4GS Luxury suspension including the rear coils, rear shock absorbers, and the front and rear sway bars were identical part numbers.

It cost me around $3k to retrofit the original 2013 4GS Luxury front coils and front shock absorbers, while I saved a lot of money by buying aftermarket 18" alloy wheels rather than my friend's original 9 split spoke 18" alloys.

How are the two suspension sets ups different?
The 2015 has razor sharp steering, and surprising terminal grip, especially for such a big car.
However the 2015 is very busy and tiring on the ride.
I found that my original OEM unmodified 2015 4GS only rode well on smooth roads; it didn't like heavily broken surfaces and pot holes.

My friend's 2013 4GS Luxury has slightly softer front coils, and significantly softer front shock absorbers, such that the turn in is good, without being razor sharp, while the terminal grip is quite good, without being limpet like for such a large car as the 2015 4GS Luxury is.
Where the 2013 suspension is very different is in the front shock absorbers and the damping; the 2013 is significantly floatier with what I describe as a "glide ride".

I have also tried mixing my 2013 retrofitted front suspension with the new 2015 19" alloys.
Here, my car has an in between compromise.
The steering is much sharper, and prodigious terminal grip.
However the ride is still floaty courtesy of the original 2013 shock absorbers.
The downside, is that the 2015 19" 40 percent profile and shorter stiffer sidewall has a much more jittery ride, and considerably higher tire noise on the highway.

My favorite is still the original 2013 4GS Luxury suspension set up with the slightly softer front coils, considerably softer front shock absorbers, on 18" alloys - for a "glide ride".
You'll find that the coils and shocks affect the ride and handling much more than the tires.
The coil springs control the amount of compression and weight transfer to determine the speed of change in direction [agility/steering response/turn-in], and the terminal grip.
The shock absorbers control the amount of float, where the floatier the car, the lower the frequency of vertical oscillations for a more comfortable ride.
A well controlled ride actually has a very high frequency of vertical oscillation, and therefore feels very tiring.

At the end of the day, I realized that the 4GS is much sportier and much more "sports oriented luxury" than a genuine luxury car, and I had to accept this.
The original 2013 4GS is sports oriented luxury, while the 2015 4GS is sporting luxury!

For true luxury, I must get a Genesis or Benz E350.
I considered swapping for a beautiful riding Hyundai Genesis, but the name, styling, huge size, economy and compromised handling got me.
The E350 has a beautiful ride, good engine, good economy, and good handling, but the styling was absolutely dreadful, and on its last yard.
The 5 Series is big on the outside, but not proportionately large on the inside, while the suspension is too firmly sprung yet too softly damped, resulting in a bobby yet floaty ride around corners.
There is no perfect car.
Life is often a compromise, so something must give.

With regard to the tires, be very careful of "silicone" impregnated "green" tires.
They are low deformation for low rolling resistance [because the rolling deformation of the sidewalls is energy sapping], and very quiet, but both the grip and ride is compromised; they grip less, and actually have a bumpier ride.
I got Bridgestone ER33's for my old 3GS; they are silicone impregnated, lighter on the power steering and very quiet, but the lack of grip and the bumpier ride inducing more creaks and rattles annoyed me.
I had to sell the several months later, and buy original OEM Dunlop tires from the dealer, which were slightly noisier on the highway, but was resilient and really gripped.
.

SW17LS

My business partner has a 2015 GS F Sport, and I now have an LS460 which obviously rides great. I rode in his GS yesterday and yeah bumps and ruts are sharp, but I commented on how nicely it rode on the highway...his has Michelins.

I would do the P7s (have them on my LS) if you have Dunlops. What tire pressure are you running?

neilsarkar

Maybe I am spoilt by the current generation 535i's vault like interior (it shares architecture with 7-series), but the GS has considerably busier and noisier ride in California's ever-degrading freeways. I am looking at non-invasive ways to improve the ride.

I have Bridgestore Turanza ER33, not Dunlops. I keep them at 33 psi, as recommened by Lexus.

neilsarkar

I also should add that my GS, being a non F-sport variant, rides on 18" wheels and 235/45R18 tires - not 19" like the F-sport GS.

AJLex19

I felt the same issue with the stock Dunlop Sport 5100.

Highly recommend the Pirelli Cinturato P7's or the Dunlop Signature HP's - you'll lose a little bit of that "performance" grip compared to the Dunlop Sport/Bridgestones but the tradeoff is a smoother ride.

islandbeef

Wow, now this all makes sense to me with my '13. I concur that I feel the "floaty glide" ride in normal to Sport mode but it goes away when in Sport +. I must admit that my F-Sport felt a little floaty in daily driving conditions but I assumed it was always a "Lexus" thing. I'll drive a newer model to compare.

Thx.

neilsarkar

island, which tires do you have in your '13 GS? I can use some 'floaty glide' in my '15

Bartman619

+1. I wish some suspension manufacturer made a thicker front Sway Bar for the GS. I don't really feel like spending $$$ on a TRD one. Hopefully the GSF front sway bars will fit ours....Just waiting for somebody to try that upgrade.

peteharvey

I'm not sure if there is any difference in the suspension between the '13 versus the '15 in F Sport trim?

islandbeef

My first set of tires were Dunlop SP Sport Maxx. The car was so smooth and floaty on long hwy drives, my wife would easily fall asleep when riding shotgun. I now have the Continental ExtremeContact DW's and the ride is even smoother than before.

If I keep this up, I may move up to an LS with comfort air suspension. I'm getting old.

ryanSC300lover

iTrader: (1)

Been driving LS since my 20s (always have sports cars on the side). Tried CT, GS, Lx, nothing compares to LS for smoothness....

peteharvey

The GS F's 5.0 V8 is really heavy on the nose, so the front coils, shock absorbers and sway bars will be very different.
Fitting the GS F's sway bars onto a GS350 may void comprehensive insurance?

islandbeef

I'm with you. I split time between the GS and LS boards. The thing that keeps me away from the LS is the air suspension issues that can be a pricey fix when the warranty lapses. My wife's Mercedes GL has the same concerns, that's why I went CPO with that purchase to be on the safe side.