I decided to keep my 19" OE rims and install H&R Hubcentric 20mm wheel spacers on all 4 rims.
to give the RX a more aggressive stance. The sidewall of the Michelins are now just 3mm inboard of the fender lip, they were 23mm inboard prior to the spacers installation. The RX does not lean as much as it did before the spacers were installed. Here are some pics.

 

I've never understood the interest in doing this. I've seen many other postings about high speed vibrations caused by spacers. I understand it makes the vehicle look like it has a wider stance, but what tangible benefit is gained by doing this?

 

I assumed that this is a Lexus enthusiast's forum site and not Consumer Reports and that appearance & performance would be of some interest to some. If you wish to become more informed about the benefits, visit this site www.trakplus.com. I'm in my 60's and still maintain interest in aftermarket parts & accessories. If you wish to keep your vehicle completely stock so be it.
Just for your information these are HUBCENTRIC H&R German made spacers, 60.1mm OE fit, no vibration whatsoever. Stud Centric will cause vibration at higher speeds as well as cheaper plastic hub rings.

 

Slightly increases the lateral moment arm from the outside wheel to the center of gravity. Buys you a few more FPSS of lateral acceleration before you'd tip over if you took a turn really aggressively assuming you did not skid. Newton is writhing over in his grave right now over your lack of knowledge of mechanics (just kidding)!

 

can i ask a simple question? coming from a "regular" joe.
Replacing the stock tires with a "wider" one? isn't that better than using spacers?
instead of a 235.. say a 255.
i'll have more grip and i can attack corners better.

 

To take your sample sizes : OE 235/55/19" tires on 7.5 " rims are 29.2 " in height
and 9.25" wide

255/50/19" tires on 7.5 " rims are 29" in height
and 10.04 " wide

20mm spacers are .79 inches the difference between the
tires above is identical at .79"
so theoretically, the use of the larger tires are equal to the 20mm spacers, however you have to take into account that your ride comfort, as well as your speedo will be slightly affected but would benefit with better handling characteristics due to less sidewall flex and larger tread print, and lastly there is the cost factor, 4- hubcentric spacers cost approx. $220 vs the cost of the tires plus mounting and balancing I estimate about $630 for Yoko's at Discount tire plus balancing.
The other factor is according to Tire Rack is that a tire mounted on a narrow rim say 7.5" would be "narrower" than the same size tire mounted on a wider rim. Personally I would mount the 255's on a 8" or 8.5" rim which would necessitate the purchase of aftermarket rims as the OE rims are 7.5"'s. After all that wouldn't it be easier and cheaper to just install HUBCENTRIC spacers.

 

^ Thanks tak06. i forgot to include the rim size.

 

Well there are some negative aspects to using spacers that go along with the postives of marginal better handling. Especially when leaving the 'mild' area of between 5-10mm.

- By having the wheels out farther there is a greater chance of throwing road debris onto the side of your vehicle

- Increased scrub radius increases stress on wheel bearings

- need for longer wheel studs - hopefully 20mm leaves enough room for three treads engaged which is needed for maximum strength.

- can also weld onto the hubs in rainy climates (galvanic corrosion) unless you use lithium grease

Up to the individual to decide if worth it. On my SUV not so much. My GS, of course.

 

Wasn't trying to offend. I've just seen many others post on spacers and then have issues traced back to them. Didn't know there were hub centric ones and as DWlink explained, that makes sense. The cost savings also is a nice benefit.

My stance was like what Mark said and on my GS F I immediately upsized the tires on the front and rear for stance, grip, and stiffness in sidewall. It's your car and the stance does look good. I was just curious of any negative side effects you might have experienced.

I used to mod my cars heavily before I leased them, but found it easier for me to just spec the car the way I like it and customize the tires, get a full %20 tint all around and maybe tweak a few other things that are small. But I used to rip out the stereos, change the shocks, springs, bushings, etc. I just reached a point where it got to be less about enjoying driving and more about chasing problems from all the changes I'd made. But it looks good. Do you see.any improvement in driving characteristics?

 

I have 255mm wide Winter wheel and tire set, which accomplish the same thing.
Spacers can be useful to correct wheel offset, if it does not match stock. But on stock wheels, the suspension geometry changes, as the center of the tread is shifted outward. So, it may be a cosmetic mod that negatively affects ride quality and may cause more wear. Otherwise, looks clean. If you like it, it's all that matters. We all do many things others don't approve.

 

Subtle, but looks good! Just a little more aggressive looking.

Question - I have heard doing this changes the geometry, which throws the car off from the original design. Do you feel any difference in driving characteristics? Or concerns about how that affects traction control, etc.?

 

If anything, the vehicle rolls less on turns and has a more planted feel.
I've used H&R on many vehicles with no negative geometry nor suspension issues,
Currently using 7mm on my Z06, 20mm on son's Mustang and 7mm on his Z, in the past
20 mm on Acura TL & Civic Si. as I stated before these are all hubcentric quality spacers.
Oohpapi44 mentioned thread engagement, there should be at least 7 full turns of engagement, 3 would not
cut it for safety purposes. You will have to use extended thread nuts or longer wheel studs to accomplish this.
In my case as the pic shows, the DRM model has it's own studs protruding from the spacer, the 5 holes are
for the vehicle studs to fasten the spacer onto, therefore thread engagement is not an issue.
The RX 350 OE rims have an offset of 35mm any aftermarket wheels less than 35mm would potentially
create more stress on the bearings, not just a spacer issue, I personally never had bearing problems in the past.

 

No offense taken, and I understand fully where you are coming from (been there done that as the saying goes) During my younger days, I too made silly mods that negatively affected the driving characteristics, seems that the purpose of these mods were just to be a little unique from similar vehicles on the road and I didn't care how it drove, however one becomes a little wiser with age and thus explains why I chose not to go with aftermarket wheels/tire package, which would probably negatively affect the luxury feel of this excellent SUV., the alternative was hubcentric spacers, which I've used in the past on many occasions without any problems.
Maintains the quality OE road feel and provides a bit more stability now that the track is about an inch and a half wider front and rear, plus there's less body roll .

 

For my educational benefit, if spacers offer such improvements, why doesn't the vehicle come that way from the factory? Aerodynamics, cosmetic concerns, other?

 

Just using a 1 to 10 scale, cars from the factory are going to be set at level 5 if that is going to be the most successfull formula for mass production with the least amount of problems. Making changes to a design that push it to level 8 or 9 may give you better results in one area but will likely have adverse effects in another. The more you push, the more you give up.

Going spacers would not be the first or optimal option to achieve better handling, just the cheapest. And least effective unless you went extreme.

Lowering the vehicle
Staggered rim setup with wider rim/tire combo
upgrading suspension components
Front/Rear Strut bars

Any one of the above will provide a real difference in changing the handling characteristics (notice that I did not say improve, just changing) for street application. But lets say you do put on a spacer that is large enough to where you notice less rolling. It's an SUV and designed to have roll to avoid flipping, that stress is going somewhere and the only upgrade you've added is ?...

I am not knocking spacers at all as I run them on my GS, but if adding them for looks, just add them for looks and leave it at that, drive the SUV like an SUV. There are pros to adding spacers, but there are cons as well and my point is that the conversation should not be simplified to where someone is just going to pick a number (5mm, 10mm, 20mm) out of thin air, slap them on a vehicle and declare it 'better' than before.

"Never enough time to do it right, but always enough to do it over"