Grantville

Hello all!!

Just acquired my third Lexus GS300 a 2002 Gold/tan with the NAV & Levinson and 16" chromes.

The car has 76k miles has had all the service done at the dealer and they did the timing belt & water pump in 2008 and all the service based on time vs miles, stamped the book.

I am suprised that the 2002 is improved in the comfort and handling as compared to the 1999. I know the car was updated in 2001 but had no idea of driving dynamics improvement.

I plan on keeping the factory 16" 215/60/16 tire and wheel combo. As this car will be used for daily driving, along with my Ram Diesel, with pot holes, wavy black top, and my 1/4 mile gravel drive.

The car has the dreaded steering wheel vibration and is ready for new tires. My tire thoughts are the Michelin Primacy or Khumo Platinum, based on reviews of lack of vibration, etc.

I plan on doing the complete Daizen Bushing, control arms, steering rack, tie rods & lower ball joints. I also want to do the "caster arm bushing kit" but did not see that available for order on the web site; I emailed them asking to include this. I also plan on the Blue TRD sway bars and tighting the steering adjuster about a 1/8 of a turn.

The big questions, since I am going to be into the suspension so deep should I at this time replace the stock springs and shock/struts. The factory original seem to be in very good conditon for 76k miles, but they are obviousily 8 years old with the 76k miles.

Because of the reality of the roads I have to drive on, I want the car to handle better but still maintain close to the stock comfort level and lower the car no more than an inch in ride hight.

OPTION #1 - Leave the stock springs and stocks in place at this time.

OPTION #2 - Replace with OEM springs and shocks.

OPTION #3 - Repace with aftermarket spring/shocks. Possible L-tuned combo or other after maket combo. I have eibach/kyb combo on my 1999.

OPTION #4 - Go with coil overs! The low end price options are the Megans, the Tein Basic Coil overs, and BC Racing. The pricey choice would be the Tein CS Coil Overs (comfort spec)

A. Megans seem to have conflicting opinions, and "rumored" to made by BC

B. Tein Basic Coil overs - I have read no opinions on these.

C. Tein CS Coil overs - sound like a great choice but $$$$

D. BC Racing Coil overs with custom spring rates similiar to the "Tein CS"

First, Am I making a good choice in the Tires?

Second, Am I making good choice with the Daizen kit and TRD blue sway bars.

Third, assuming that my choice in Tires-Diazen-TRD is good.

What about my Shock-Spring-Coil Overs options??

ZippyGuy

iTrader: (9)

A gigantic question you're asking, but given your preference of "....want the car to handle better but still maintain close to the stock comfort level and lower the car no more than an inch in ride height," I would recommend the following:

Option #3: Tanabe NF210, Eibach (my personal preference considering the lifetime warrantee, or L-Tuned paired with KYB, Bilstein (my personal preference considering the lifetime warrantee), stock struts.

Given the harsh roads you're driving, no need to try to profile by "going low," and your need to retain most of the factory ride I think this is the way to go. Once you install the Daizen package, not to mention the TRD sways, your ride WILL become more harsh so a mild drop should be most appropriate. Also, if you're adept at doing the work yourself this combo will be the most cost efficient.

GSteg

iTrader: (15)

I 2nd going with Eibach/Ltuned or even Tanabe NF210 springs. The Daizen bushings and TRD sways are definitely going to make your ride less Lexus-like. I had the same setup with L-tuned springs and eventually sold off my sways and bushings. The TRD actually wasn't harsh at all until you hit really bad potholes, but the Daizen bushings drove me nuts.

If you have to get coilovers, go with BC Racing coils with their softer 8k/6k setup. Tein CS is comfortable but the price that they're wanting for a new set nowadays is simply overpriced. And yes, Megans are made by Bor-Chuan (BC), and no, I would not buy them if you can get a nicer setup for a bit more.

Grantville

Harshness of the Daizen?

It is interesting the difference of opinion on this issue, it is so subjective. The many comments that the complete Daizen kit helps to solve the dreaded vibration are what impress me. The vibration drives me crazy and it makes sense that the movement caused by the rubber components contributes to this. I would think that with quality and in very good condition shocks/springs and tires that would be minimal.

The few coments regarding the harsness has me concerned. But, there are many folks who say this is the best thing they have done and it helped the vibration.

Ah, what to do?

GSteg

iTrader: (15)

It depends on your tolerance. Lots of guys who thinks they're the greatest thing since sliced bread are the younger crowd with 20s, driving around on rubber band tires and are dropped on coils with high spring rate. You won't feel that much of a difference if your car is already bone jarring. On a stock car, you'll feel the increase in harshness. I had vibrations too, but the the kit didn't fix the problem and it ended up being something else. I don't have any more vibrations after changing out my tie rods and adjusting the steering rack. Of course your situation might be different but if I had to do it again, I would buy OEM 01+ lower control arm (caster). This bushing is what causes the most of the vibration in the first place.

CircuitMS

iTrader: (51)

If you decide you want to go with a set of coilovers shoot me a PM and I can help you out on getting a good DD setup.

There are also the SPC front upper arms which allow you to adjust caster and camber, if you're looking for that as well.

tither777

iTrader: (4)

i have the vib at 55-60 VERY mild with stock rims, just put on some 20" for the look and boy did it shake at the same speed…. was told to change out bushings Daizen is NO WHERE to be found. so i am buying the stock caster arm, lower ball joint , and tie rod ends…… BUT WHAT IS THE STEERING RACK ADJUSTMENT YOU ARE TALKING ABOUT?????

Grantville

Tither, Always cool how these shake thread come back to life.

I will give you my take and then you can be the decider.

I live in the country outside of Topeka Kansas

I have a 99 GS300 with 160k and a 02 GS300 that I bouht in August with 75k one owner miles that I did work on. I did the 6 year 90K service under the hood, timing belt, water pump, new belt pulley & tensioners, all hoses & belts, plugs, wires, and battery. This is the exact same work I did when bought the 99 w/90k. I have done nothing on it except oil & tranny every 15k and brakes/KYB struts. It is remarkable how solid the 99 still is, as the wife drives it and is a little hard on it. I have a second set of 16" wheels with winter tires for both cars.

Suspension on the 02:

I did the works immediatly as I wanted to get the best ride/drive/handling care I could for the the next 70-80k miles.

Springs:

I did the Tien H-tech springs, I did this for the mild ride hight drop so I miss curbs and dips and to get a much better handling care with only a slight decrease in ride quality. I got exactly that! I have Eiabach springs on the 99 and it sets lower and can hit parking stops and bumps.

Suspension:

I did the complete Diazen bushing kit from Todd at TM engineering including the sway bar bushings. Additionally, I replaced the control arms for the ball Joint and replaced the new bushings w/Diazens. I also did new Raybestes Ceramic rotors and pads. Then I took it to a locally owned alignment shop.

Tire & Wheel choice:

I have stock with the stock chrome wheels my car came with. My tire choice is 235/55-16 General altimax. I did not install them until completing all suspension work and the alignment. I am tickled pink with this combo with the springs I choose. I have a car that from front and rear have 235 with tires that look very good. The side view results in a very narrow wheel well gap. Yes, it may have been cool to go with 19 or 20s but I got the "look" and have a care that drives and rides awesome. A great choice for a daily driver!

Steering rack adjustment:

This adjustment may be beneficial, but I went about 1/4" and it was dangerous and stupid go kart like. I put it back to the original marking plus maybe a 1/16". The steering quickness is very good at this adjustment amount. The amount of adjustment IMO is dependant on the car and condition as to the amount of adjustment the car and you want.

The "shakes":

IMO, these cars are by nature very sensitive regarding steering vibration. It is their "flaw" my 02 had/has it much worse than the 99 ever did. IMO, my conclusion is that yes the suspension stuff helps a little. But, the shakes are cured by wheel balance. In another thread went into much detail about this.
But with the 02 I tried all three sets of tires/wheels I had and the vibration was different on each. A local tire shop "Performance Tire" that has tech's with 30 years experiance put their effort into balance the tires. They mounted the General 235/55-16s with their latest and greatest laser balance machine(which is at a branch location) and the result showed the tires in balance. I drove the car and crap it was the worst vibration I could imagine. So, I took the car to the main location talked with the 2nd generation ower and we took a spin. His reaction was "****" this is bad and not acceptable. We pulled the tires and wheels and put them on his "hunter road force" machine, which is older technology than the laser machine. The tires read perfectly in balance. Needless to say I was disappointed and Justin the owner was shocked. So, to my suprise he said he said lets strip all the weights off and start over. The laser machine had print outs of before and after the balance. The result of the hunter road force balance(remember it read in balance) after we started over was with weights in different places! The result of was a car that was smooth, not perfect on wavy asphalt roads and perfect on new concrete interstates. Justin, the owner, in his opinion stated that this car was the most sensitive car as far as wheel balance that he had every experianced. Hell, I still have a hard understanding the balance issue.

Summary:

These cars are sensitive! Some worse than others, why I am not sure anyone knows. If lexus could fix it , I am sure they would have. As such, some cars may be undriveable with larger diameter tire and wheel combinations. If you car is a daily driver and you have the severe vibration issue, stick with the best looking 16" factory wheels you can find and use 235/55 for the "look"

tither777

iTrader: (4)

thanks…. very helpful...