7asteroid7

Can anyone tell me what tire size I'm supposed to buy for 20 inch rims? I was told 235/30/20, but I want to double check with you experts.

I'm planning to buy a suspension kit too. Will I need low profile tires?

Thanks.

leestoy

What Car Is This Going On..... If It's A Gs.. I Would Recommend 245/30 And 285/25... Just My $.02

Aristo300

A 285mm tire in the back would depend on whether or not the wheels are staggered. 275/35/20 is more prevalent.

jwin

iTrader: (16)

it would help if we knew the tire width cause that would depend on what series tire you would run i had this big problem just not to long ago....

jwin

iTrader: (16)

i have a 9.5 inch rim in the rear and i am running a 265/30/20 and a 245/35/20 in the front on a 8.5 inch rim

Neo

iTrader: (3)

We will need more specs. What's the width, i.e 20x__ ? What's the offset? If the wheels are staggered, we will need the specs for the front and rear.

"suspension kit"? You mean you plan to lower the car? How much lowering? "low profile tires"? Once you are past 17s for the GS, you are in the low profile domain. So for 20s, yes you will need low profile tires.

7asteroid7

Thanks everyone for your input.

These are the wheels I'm buying. The seller isn't giving me any specs, just that they're 20 inches and that they'll fit my '05 GS430.

This is my first time modifying a car, so I really don't know much about what I'm supposed to do. I read in a post here that 20" will cause the speedometer and the nav system to be off. Is this true? If so, any way to correct it? I have a heavy foot, and it wouldn't help if the speedometer says I'm only doing 90 when I'm really closer to 100 mph.

I'm planning to lower the car about 1.5 inches for aesthetic purposes after I install the big wheels, but the same post says that if I do that, the tires will rub every time I go over a pothole or uneven road, also when the steering wheel is at full lock and backing up. Is this true? I want to make my car look good, but it sounds like 20" involve a lot of headaches. Your input please.

Finally, what brand do you recommend? Toyo/Yokohama/Falken? I was told these are all priced similarly.

Thanks once again.

Neo

iTrader: (3)

It is somewhat difficult to say with absolute certainty without the specs. "Fit" means different things to different people.

This is due to the fact that for a long time, only certain size tires were availalble for 20s on our car. The most typical size caused the overall diameter to become about 1" bigger/taller than the OEM size. There are a few manufacturers that now make tires that will keep the diameter at or close to OEM. The frawback on this is that the tires will be really "thin" which makes for higher potential rim damage and harsher ride quality.

Again, wheel specs (offset, width) would help here but yes, the wheels may do that.

There is a saying that floats around about modding: "You've got to pay to play." Yes, this typically refers to monetary costs. It also can refer to the compromises you make to look good.

7asteroid7

Money's not really an issue, but the speedometer and nav being off, tires rubbing all the time... that does sound like a headache. I guess I have to compromise, yes.

I purchased the wheels online. I'll post specs once I get them, hopefully you can advise on what tires to buy.

Thanks for all the info.

Neo

iTrader: (3)

Rubbing and speedometer/odometer issues or ...
It just depends what you can live with.

RMMGS4

iTrader: (5)

You CAN achieve the correct speedo on 20's and mod the car for NO rubbing at all, but you haven't given us the specs on the wheels, which is the determining factor for our answers.

Unless we can get the specs the answer is "maybe".

Since you are already committed to these wheels regardless of spec, then your destiny is atleast partially determined, because we might not be able to resolve certain issues such as rubbing if the offset is too far off.

Odds are that most wheel manufacturers are conservative with offsets and you will be safe. Also I expect your seller would set you up with an appropriate fitment specifically for Lexus, so again you could be OK.

When choosing the more expensive 3 piece wheels, it is imperative that you design and order the wheel to a specific spec, with tire size, BBK clearances, rim width and offsets all factored into the equation.

D2-AUTOSPORT

Without knowing just the basics (like the width) its hard to say what will and will not happen. It sounds to me like the seller is giving you a "off the shelf" recommendation, meaning they recommend that tire so if fits eveything that they sell off the shelf. That tire has nothing to do with a GS unless your running a wicked VIP setup with insanely low offsets etc. If you put that tire on a 20x8.5 with normal spec's then its going to look like you have Honda Accord sized 20s on your GS.

20's are as easy as pumpkin pie, so dont let anyone deter you if thats what you really want.

Brandon@TR

The correct 20 inch size is 245/30 20 and that will fit on anything 8-9 inches wide.